After the Second World War, Detroit was triumphant while Berlin and Tokyo lay in ruins. Today, however, failures in urban planning have left it the one looking war-ravaged. To rebuild, Motor City needs to welcome back the pedestrian and rip up its motorways.

During the Second World War, Detroit was the most productive city on earth. America and its British and Soviet allies won the war with Detroit-made tanks, Jeeps, guns, planes and ammunition. In August 1945 the city stood triumphant. Its centre, packed with pedestrians, held three department stores including Hudson’s, which was about the size of Harrods in London.

In 1945, much of Berlin and Tokyo lay flattened, as did Hamburg, Dresden, Nagasaki and Hiroshima. Today, all these cities have been rebuilt. Now it’s Detroit that lies in ruin. The department stores and all but a few pedestrians are gone. If a person unaware of 20th-century history viewed Detroit and Berlin and was asked which city was the epicentre of the world’s most destructive war, their answer could only be Detroit.

What happened? There are, no doubt, many factors; over-dependence on a declining auto industry and racial disharmony are often cited. However, I attribute the steep decline of Detroit to one of the most colossal public-policy failures ever: the US’s road-building programmes as applied to cities.

For decades, transport agencies have pursued the goal of conquering congestion. To accomplish this they’ve designed roads exclusively for vehicles. In an urban context, this was a stark departure from the time-tested practice of building streets with three purposes: movement, commerce and social interaction. The great modernist Le Corbusier famously said, “Kill the street”, meaning get the pedestrians and pavement cafés and other obstacles out of the way of traffic. His prescription for Paris would have created bridges and underpasses (“grade-separation”) on all major streets. His ideas were rejected by Parisians, but found a home in US traffic manuals. When applied with separate-use zoning, these policies create what Americans call sprawl.

This focus on big roads is a key reason we’re so dependent on foreign oil and it’s the biggest single cause of our enormous carbon emissions. In Detroit, almost every motorway ever dreamed of was built, while the street network was degraded and transit removed. This reduced congestion but the side effect was fewer jobs, businesses and people.

Some North American cities resisted the big road policy. Jane Jacobs helped block motorway construction in New York, Boston and Toronto. Recently, cities have begun removing grade-separated roads and restoring avenues, boulevards and streets that serve not just as traffic conduits but also as the setting for jobs, shopping and living. In San Francisco in the 1950s the Embarcadero was covered by a two-deck motorway that collapsed in the 1989 earthquake. Soon after, the Embarcadero’s original boulevard and tram lines were restored and now help traffic distribute more efficiently, adding investment to the area. These streets form the spines of walkable, mixed-use neighbourhoods with jobs in the environmental sector and convenient living (see also our Abandoned Cities feature, page 33).

The “big road” policy failed America’s cities, but change is on the way. Organisations including the Institute of Transportation Engineers and even the US Federal Highway Administration are open to restoring urban street types to road design manuals. People are increasingly attracted to urban living and with the environmentally conscious Obama administration looking to change failed policies, now is the time to insist that, instead of battling congestion, it must be managed. It’s also time to insist that transport investments enhance places.

A great test of the success of the Obama administration will be what happens in Detroit. The once great Motor City, damaged by bad public policy, can be rebuilt just as the war-damaged cities of Europe and Japan were. But first Americans must reject Le Corbusier’s advice and instead of killing the street, revive it.

Monocle comment: It’s great to get people out of their cars and onto their bikes, but not before there are adequate cycle lanes (London take note).

If many modern urban planners had their way, the city would be divided into strictly designated zones for living and working with little opportunity for chance encounters, surprise and, above all, sauntering. Cities that embrace the modern flâneur are those that allow for a little chaos – and are all the more attractive for it.

For all that we might claim to value quiet, privacy and acres of fenced-off space, one of the finest experiences of city life is to be squashed up against hordes of noisy strangers on a busy piece of asphalt. After too long in solitude or in the claustrophobia of the office, there are few more intense pleasures than to head out for a swim on one of the world’s great thoroughfares, to take a dive into humanity on the Bahnhofstrasse, Madison Avenue or the Boulevard Saint-Germain – and for a time to gain relief from the narcissistic claims of the ego in an unimaginably diverse ocean of one’s fellow human beings.

As we advance down a thoroughfare, amid the colours, the noise and the smells, the shopkeepers of the great city streets will strive to capture our jaded interest with the most fanciful advertisements and displays, while out on the car lanes, pulses of murderous traffic negotiate their way past us. However quintessential and pleasurable such scenes might appear, if modern urban planners and engineers had their way, this sort of chaos would never be tolerated. The ideal city would be one where all functions – eating, working, sleeping, socialising, raising kids – would be separated out and located in unique zones connected by motorways and train lines.

The ideal city would be Dubai rather than Paris. But urban planners always lose sight of the benefits of chaos. They forget that without pedestrians to slow them down, cars are apt to go too fast and kill their drivers, and that without the eyes of cars on them, pedestrians can feel vulnerable and isolated. Cities laid out on apparently rational grounds, where different specialised facilities – houses, shopping centres, offices – are separated from one another across a vast terrain connected by motorways, deprive their inhabitants of the pleasures of incidental discoveries and presuppose that we march from place to place with a sense of unflagging purpose. But whereas we may leave the house with the ostensible object of visiting a colleague in an office, we may nevertheless be delighted on the way by the sight of the fishmonger laying out his startled, bug-eyed catch on sheets of ice, by workmen hoisting patterned sofas into apartment blocks, by leaves opening their tender-green palms to the spring sunshine, or by a woman with chestnut hair and glasses reading a book at the bus stop.

For traffic engineers in danger of ruining our cities, Charles Baudelaire (1821-1867) may be the perfect guide to reforming their profession. In his prose and poetry of the 1850s and 1860s, Baudelaire described walking down crowded and diverse city streets as one of the most exciting adventures open to mankind, far more dramatic than any play, far richer in ideas than any book. And he settled on a word to capture the attitude he felt one should adopt when walking along the streets. One should become, he suggested, a flâneur, translated literally as a stroller or saunterer, though Baudelerians normally keep it in the original.

So what do flâneurs do that ordinary people on their way to work wouldn’t normally? Perhaps the defining characteristic of these flâneurs is that they don’t have any practical goals in mind. They aren’t walking to get something, or to go somewhere, they aren’t even shopping (which is as near as most of us get to this Baudelerian ideal). Flâneurs are standing in deliberate opposition to consumer society, with its two great imperatives – to be in a hurry and to buy things (as a protest against the former, there was in Paris a brief vogue for flâneurs to amble around town with tortoises on leashes).

What the flâneurs are doing is looking. They are opening their eyes and ears to the scene around them. They are not treating the street like an obstacle course to be negotiated, they are opening themselves up to it. They are wondering about the lives of those they pass, constructing narratives for them, they are eavesdropping on conversations, they are studying how people dress and what new shops and products there are (not in order to buy anything – just in order to reflect on them as important pieces of evidence of what human beings are about). The flâneurs are avid enthusiasts of what Baudelaire called “the modern”. Unlike so many of Baudelaire’s highbrow contemporaries, flâneurs aren’t just interested in the beauty of classical objects of art, they relish what is up to date, they love the trendy.

It’s a paradox of many modern cities that though they bring together huge numbers of people in small spaces, they also separate them from each other. So it’s the goal of flâneurs to recover a sense of community – as Baudelaire put it, “to be away from home and yet to feel everywhere at home”. To do this, flâneurs let down their guard, they empathise with situations they see, there’s a permanent risk they will be moved, saddened, excited – and fall in love. Baudelaire’s poem “À une passante” in Les Fleurs du Mal is one of the finest poems on the mini-crushes one can – as a flâneur – develop in city streets: a man walks past a beautiful woman in a crowded thoroughfare. He sees her for only a few seconds, she smiles at him and he is filled with longing and a sense of what might have been. The poem ends with the sigh “O toi que j’eusse aimée” – “you whom I might have loved”.

It can be hard for mayors and city authorities to make a rational-sounding case for something as apparently frivolous as being a flâneur. It sounds more normal to argue the case for a new hospital or traffic lights. And yet when we think of cities that work well, and that in turn attract real money, they tend to be the ones that are unafraid of a bit of chaos, that are aware of how much we value streets that throw us up rudely against our fellow humans; cities that know that a little mess, entanglement and inefficiency is really a chance for us to exercise our curiosity and humanity.

Monocle comment: Individual statement buildings are the undoing of potential flâneurs in the Gulf cities. Planners forget it’s what lies in between that matters.

It’s the end of the century and a man and his son stand on a hilltop at dusk. Beneath the comforting throb of a 100-storey-tall wind turbine, they look out over the landscape; a patchwork of fields and hedgerows, small farms and villages. Cattle graze in water meadows next to a lazily snaking river while combine harvesters rumble back to their barns, leaving golden fields shimmering in the reflection of acre-wide solar panels and balmy harvest dust.

As they squint toward the horizon, the men can make out the silhouettes of a collection of preserved ancient buildings, an Olde Worlde architectural themepark: a glass and steel skyscraper crowned by the flickering logo of a long-forgotten banking conglomerate, a crumbling tower block leaning as if it belongs in Pisa (where there was once a famous tower), a shopping mall rising from a deserted car park, beside it a single pylon. “All these fields,” says the old man with a sigh, “I remember when this was all factories.”

Sounds idyllic, but this used to be a big city. Where did it all go wrong? How do you save a city from going to seed? To start, be a city in the first place. Be civilised. This means more than knowing which bit of the opera not to burp in; it means good schools, vibrant street life, industry and infrastructure, art galleries and abattoirs; a sports team that has an arch rival; hotels and hospitals equally renowned for their rejuvenating qualities. It means making a place that attracts outsiders while encouraging homegrown talent, championing enticing architecture to go with inevitable earthy urban decay. It means tending the shy shoots of artistic endeavour, being glad that cabbies deem Damien Hirst a charlatan over having not heard of him at all; it means a generation of kids growing up not wanting to be train drivers.

Culture is key; art is vital – especially when it makes money rather than just spending it stylishly. But it’s the buildings that contain this culture that draw the crowds and the people that direct them who should be running the cities in which their museums sit.

Museum directors are savvy hustlers for high-quality exhibitions and international recognition balanced by a responsibility for big budgets and a spot of myth propagation – not a bad bet for a local leader. Behind the scenes at the museum are ambitious chieftains with one eye on attendance figures and the other on (art) history – their museum’s and their own.

Museums are totems of success and civilisation designed to reflect not just the intent of the art within but the challenging modernity, intellectual rigour and newfound creative playfulness that a museum, especially a museum of contemporary art, embodies.

Cities love it when their art collections are refreshed with a bit of architectural gift-wrap, rebranded in a clean-cut context, in spotless white cube interiors the size of icebergs that scream silence, that noisily let the art speak for itself. But then there’s the show – the exterior. It’s all very well mooning around in a cloister full of Rothkos but if the place they’re in looks like an armadillo fucking a pineapple, so much the better. After all, how did they get it to stay up?

Way back in 1997, when Bilbao got its Guggenheim plugged-in, it found that tourists from around the world turned up to its unfamiliar industrial city to gaze at Gehry’s shiny marvel. Juan Ignacio Vidarte, the Bilbao Guggenheim’s launch director, watched the foundations going in years before seeing the paintings hung. Vidarte’s commitment to his hometown and belief in the attraction of his grand project make him a strategic giant who you could easily imagine running the whole city, if that job weren’t so confining. Abu Dhabi’s island of art on Saadiyat has been built to recreate “the Bilbao effect” in the emirate, it’ll come complete with its own Gehry Guggenheim – a foreboding cultural megastructure in the now familiar style. And you’ll go, won’t you?

Museums serve as exemplary accidental piazzas; talking shops, communities, nights out, pick-up joints catering to the sort of people who want to engage while they’re enjoying a cocktail. If museums were microcosms of cities, there would be some Arcadian urban settlements run by hard-nosed but imaginative planners passionate about their cause. Andy Warhol was adamant that the best art was good business. Perhaps a town that combines the two would be t­he very best place to live.

Monocle comment: The Gulf projects are to be applauded for creating spaces where people will be forced to meet as equals.

Last autumn’s financial meltdown means there’s less money available for public buildings. This must lead to a new way of thinking about infrastructure in cities and a whole new kind of architecture. This could be a case of opportunity arising out of crisis.

The new era in architecture began last autumn, when the world’s financial markets imploded. The world of architecture as the US knew it – boisterous new buildings, cranes on every skyline, unlimited budgets – came screeching to a halt. An era of bombastic, willful and self-centred architecture has changed to a new sensibility that will characterise architecture from now on.

So what does architecture need to become? New projects must now embrace the aesthetics of austerity and make a virtue of economic necessity. Beauty must be a function of simplicity, composition, and quality rather than expensive materials or structural gymnastics. Architects must do more with less. The new architecture of austerity demands a redefinition of the sorts of projects we even consider worthy of the question, “Is it beautiful?” Promised improvements to our national infrastructure must have a vision for their physical presence.

While we should applaud the Obama administration’s commitment to spending on infrastructure, we should be made very nervous about the concept of “shovel-ready”. It can only mean no time went into thinking about what it looks like. To paraphrase Einstein, you can’t solve a problem with the same kind of thinking that created it.

Infrastructure is important enough for us to care about its physical form. That requires a stunning shift. It means talking about museums and hospitals rather than access roads to green-field McMansions; schools rather than highways, and soaring bridges and train stations rather than mundane road repairs and widenings. It means including what is required by citizens of a civilised country: parks, schools, libraries and housing. The list of “what is infrastructure” must be expanded to enrich its aesthetic potential. Financial constraints can lead the masses to appreciate the beauty of projects that come under the prosaic rubric of “infrastructure”. Infrastructure deserves an aesthetic and one that exalts austerity. Think “back to basics” with a twist of social responsibility. Think about Utopia.

Monocle comment: Idle cranes around the world offer a real breathing space and one where developers without passion can hopefully find new careers.

After Israel was founded in 1948, the speed at which it built towns for the influx of refugees meant that town planning was often rushed. Today, there are simply too many towns and cities without adequate services. It’s a warning about the corrosive power of sprawl and homogeneity.

Since the state of Israel was created in 1948, its great challenge has been to provide a home for massive waves of immigrants and build an economy that would allow them to flourish. It has achieved this goal, beyond anyone’s expectations. This small country is now home to over seven million people living in 220 towns and cities and over 850 small towns and settlements.

And yet, most of these cities barely function. Many have such a low population and are so spread out that they cannot prosper or provide a decent quality of life. The unique situation in Israel arises from the fact that it has always concentrated its efforts on quantity not quality of its urban areas. Almost every square kilometre of Israel’s land is populated: 92 per cent of Israelis live in an urban area. There are historic reasons for this situation.

Most of Israel’s cities, except for the centres of the old cities, were planned and built by government planning offices between 1950 and 1970 for the purpose of settling all the Jewish refugees who came to Israel from Europe and Arab countries. In those years planning in Israel and the world was of the “modern urban planning school” which combined the ideas of Ebenezer Howard’s Garden City with the ideas of Le Corbusier. The modern outlook, combined with government planning, created uniform solutions that were replicated quickly wherever the government decided to establish a town.

With time, the pace of construction slowed and the focus shifted to improving the quality of the dwellings themselves. But the urban planning stayed “modern planning” but with a new addition: suburbs with single-family, detached houses. The result is towns and neighbourhoods that are very similar physically and with nothing unique except perhaps the type of flowers the municipality chooses to plant at the sides of the road.

Not only does this mean poor quality of life for city dwellers. But the urban sprawl has eaten away at the country’s rich farmland and open countryside. Israel has less of that type of land per capita than almost any other country. And its population is growing by 2 per cent a year, which means, if the urban planners don’t have a serious rethink, the situation will only get worse.

I am frequently asked: how can we transform failing cities into thriving cities? Everyone is looking for the quick fix and too many consultants rush to oblige by proposing projects such as wider roads, more green spaces or private detached housing neighbourhoods exclusively for the wealthy far from the failing towns.

But there is no magic formula. In Israel, more perhaps than elsewhere, the geography and the population are so diverse in each town or city that any planner has completely different physical and social factors to consider.

Beer Sheva, on the edge of the Negev desert and spread over an enormous area, has a neglected historical centre and a population that includes generations of Jewish immigrants from all over the world as well as a Bedouin population who live in and around the city. Kiryat Shmona, founded in the 1950s, is at the most northern point of Israel, surrounded by green mountains. Its population is made up of immigrants from North Africa and the Soviet Union who arrived in the 1990s. Netanya, on the Mediterranean coast, has wide, white beaches. But over the years it has spread inland, with a commercial centre far from the city centre that’s accessible only by car.

There are some things, though, that all cities should consider. We come to cities in order to enjoy more opportunities. And the more densely populated a city is, the higher the chance of encounters that can lead to economic and social opportunities. This does not just mean a high concentration of residents. A city needs a variety of different people in order to build the relationships of buyers, sellers and creators.

This is why buildings and homes have to be planned to suit a mixed population of different ages, incomes, nationalities and religions. And planners need to make sure there are offices, residential areas and shops in close proximity to each other.

Walking is the most efficient way to move in a city. It allows us to reduce energy use, air pollution, noise and improve our health at the same time. It is worthwhile to plan streets with different qualities in order to create a changing and interesting experience for pedestrians. In Israel, streets need trees to provide shade from the sun.

While vehicle access is necessary, it should not determine the design of our streets as it does today. In places where space is at a premium, the needs of public transport and pedestrians should lead the design, allowing private cars access, but not speed. Investment in culture and architecture is also essential.

And finally, of course, a high quality of life can only be sustained in cities and towns that are prosperous, well managed and that can supply a broad array of services, educational opportunities, entertainment and culture. Tel Aviv is the one place in Israel that has achieved this.

Following the development of new cities in Israel, Tel Aviv was neglected and the residents started leaving. Since 1985, the city has been going through an intense restoration and preservation process. It’s credited as the first, and almost only, city in Israel to deal with urban renewal through proper management of the city. Tel Aviv is thriving due to its flexible and walkable urban planning, higher density and varied population.

Most of the cities in Israel do not meet even one of these requirements. But since Israel’s population is growing, most of the cities and towns could go through a process of renovation, adopting these principles, and positioning themselves for success.

It is a unique challenge in Israel, where there is such a rich mixture of cultures, religions and terrain. But could it also be a key factor that could ensure the whole country prospers?

Monocle comment: While Israel may not be a beacon of urban planning, it has signed up to the Better Place electric car network.

If it ain’t broke, don’t fix it... Some of the best ideas for improving a neighbourhood are surprisingly old-fashioned. Modern urbanists should visit any street in Istanbul, with its grocery deliverymen and junk collectors, for inspiration. They would also learn why a rope and basket could come in handy in a modern housing development.

My street, Kumbaraci Yokusu or “Banker’s Hill”, is near the famous Galata Tower in Istanbul, a landmark on the city’s skyline since 1348. The street slopes down towards Tophane, a stretch of Bosphorus shoreline where, interspersed among ageing dockyards and Ottoman mosques, narghile cafés and the Istanbul Modern gallery are now the attractions. My building and those around it date mainly from the early 20th century. They are modest in scale at five or six storeys, and have for decades been inhabited by Turkish, Arab and Kurdish families. To outsiders, life on my street looks frenetic, chaotic even, but there’s a simplicity and cohesion here – in everything from how people look after one another to how you get your food shopping – that could teach many western cities a trick or two.

Among the groups who live on Kumbaraci Yokusu, and whose roots are in villages not cities, public intimacy signals the cohesion of their community. You see it in gestures of respect shown by the young to the elderly and the way that people finish their chores just outside the front door, rather than pulling life inside to the privacy of the living room sofa. This means noise is everywhere – not racket, but certainly clamour. It’s the scarcity of cars that also lets street life thrive. Before and after school, children spill out on to the road. Boys kick about blue and yellow footballs – the colours of the Fenerbahçe club; while girls draw on the pavement and invent games. Not since the 1950s have children in such numbers been allowed to master the streets of western Europe’s capitals.

Meanwhile in teahouses the men – retired or jobless – crowd around backgammon boards, while always keeping one eye on the television. The figure of a woman can be seen in every window. And if she’s not in the window, then she’s on the balcony, hanging bed linen and stockings from the washing lines strung tautly between the buildings. When the washing has been hung, the work of meal preparation commences in the early afternoon.

Food and supplies move vertically and efficiently using a system of baskets on pulleys. The grocery lists are first lowered down from the windows to the waiting hands of teenage boys who have begun their “traineeships” at the local shops. Really, they’re just helping out their fathers. Filling the orders would seem easy enough, but when the vegetables begin their ascent, the shouts of haggling rain down. No one bargains harder than grandmothers. Their certainty as to the weight of aubergines in a basket – down to the gramme – boggles the mind. Shopkeepers take to the street, accompanied by their fledgling errand boys, to engage in the arguments. The pageantry of it all is a spectacular neighbourhood institution.

This is something different entirely from the scramble for produce at the weekly markets in other cities, which at times can be as frustrating as the after-work frenzy in a Carrefour check-out queue. And while in other cities supermarket chains may now boast about their home delivery services, they still don’t compete with this. And surely those baskets and pulleys could be tweaked for use on an apartment block in Portland or Perth?

Two other institutions of the Turkish neighbourhood enter the sonic landscape: the mobile greengrocer (sebzeci) and the junk dealer (hurdaci). Moving slowly through the streets in his truck, the sebzeci calls out at regular intervals to make residents aware of his presence. When I hear his yell, I usually run downstairs to see what he has today. If I only need the odd tomato or onion, I’ll drop down the basket with my order; but if I want a few fruit, then I’ve got to catch him before he drives off.

The occasion always goes beyond the commerce at hand to getting the gossip of the community. He bemoans the venality of politicians, while I get recommendations for a new barber. Through the chatting, the produce man weighs the goods and keeps a mental tally. Meanwhile, I watch the weighing and do my own tallying, in anticipation of the final negotiation on a rounded-off price total. This is a dance we’ve been practising for months.

Junk vendors, or hurdaci, may seem an even quainter fixture but their purpose is highly functional. They facilitate the rotation of daily items – this is the Turkish version of Freecycle, or a more intimate eBay. In the bed of his wooden push-cart, he might have a broken overhead fan and a pile of magazines. Often the stack of stuff can patch the holes in the hardware or stationery needs of residents. At other times, his vehicle is a veritable antique shop, freighted with wonders to make García Márquez’s Melquiades jealous. The concept of the hurdaci is based on people only getting rid of the old once they’ve found a replacement. It also helps keep the landfill sites hungry.

So perhaps the next time the world’s mayors go on urban fact-finding missions, they should avoid the trek to the latest sustainable, green community and come and steal some ideas from my street. We could all do with a neighbourhood hurdaci.

Monocle comment: Before we get carried away, let’s be honest, Istanbul still feels like a city that’s lacking an urban plan. It will be a while before it gets in our top 25. But does it have every opportunity to become a great hub once again? Very much so.

London has once again topped an internet poll as Europe’s dirtiest city, an epithet it has borne since the 17th century. Should its residents be embarrassed by the filth and chaos, or is it a cause for celebration?

London is undergoing colonic irrigation. Everywhere water company placards proclaim that they are sprucing and sluicing the capital’s “Victorian water mains” – that use of the V-word offering both a cringing admission of Britain’s neglect of the once-glamorous art of sanitary engineering, and a slap on the wrist for those frock-coated ancestors for their failure to anticipate the great volumes of cotton buds, tampons and cloacal sludge that their great-great-grandchildren would flush down the sewers.

The capital’s splayed and hunkered state is necessary and overdue. Talk to any of the salaried scrubbers who climb into biohazard suits to patrol the clogged passages of subterranean London, and they’ll tell you the saga: how they subdued the 45m-wide reef of lard that had coalesced in the intestines of Leicester Square; how a pet food firm got in touch to negotiate the stuff’s purchase and resale in kibbled form; how, therefore, the poop that you scooped in the park this morning may have contained some of the same fat that, a decade ago, was used to deep-fry your tempura.

If you’re one of the travellers who were asked by the website TripAdvisor to name Europe’s dirtiest city, perhaps this filthy story won’t surprise you. The British capital took the survey’s top position in 2009, just as it did in 2008. I detect the noise of prejudice in this data. That London is the most besmirched city on the continent has been a cliché beloved of Eurotravellers since the beginning of the 17th century. In the year of the Gunpowder Plot, an aristocratic Spanish missionary named Luisa de Carvajal rolled up in Cheapside to preach the Catholic cause and found it a dirty and cacophonous place. “At times they grind me down with the noise that comes through the wall where I sleep,” she moaned. “All you hear is the sound of meat being roasted and others cooking, eating, playing and drinking. On Fridays it gets worse.”

A hundred and sixty years later it was the turn of the travel writer Pierre-Jean Grosley to throw up his hands in horror. “I have seen,” he told his Parisian readers, “the middle of the street constantly foul with a dirty puddle, where splashings cover those who ride or walk on foot, or in coaches when their windows happen not to be up, and bedaub all the lower parts of such houses as are exposed to it.” His Italian contemporary Giuseppe Baretti concurred that “the streets are badly paved, filled with mud black as ink and with every kind of filth.” Had TripAdvisor been around in the Age of Reason, these guys would probably have set the site alight with complaints. Instead, they committed their disgust to vellum.

This history of repulsion put British sanitary reformers on the defensive. On Valentine’s Day 1901, Thomas Blashill – architect of the London County Council and builder of the Blackwall Tunnel – refuted the assertion that “London streets were the dirtiest of any to be found in the cities of Europe.” He rather blunted his point, however, by conceding that having visited Paris, Vienna, Berlin, Prague and Brussels, the thoroughfares of the British capital were the grubbiest he’d ever seen.

But there’s a counter-argument to all this nose-holding and lip-pursing. It involves the mysterious process by which oysters make pearls from specks of dirt; the growing evidence that living too cleanly does no favours to the immune system. Sterile conditions are great if you want to remove someone’s appendix or mix a bottle of formula milk for a baby. In most other human contexts, a modicum of dirt is evidence that the context you’re observing is genuinely human.

London has always prized creativity over cleanliness. As European capitals go, its development has been sporadic and unplanned. No Baron Haussmann ever had the chance to reshape its streets into an ordered, neoclassical Sudoku grid. In the 18th century, London’s artists and writers turned its rambling, stinking thoroughfares into a source of inspiration: Moll Flanders rose from up them; The Rake’s Progress and A Harlot’s Progress could not have been made anywhere else. In those days London was unregulated, unsanitary, dangerous, vital: a kind of Lagos on the banks of the Thames and the Fleet.

Victorian sanitary engineers saved us from the excesses of this state. From typhus and cholera, too. But London still seems to gain vigour from the fact that its surfaces are not as scrubbed as some of its neighbouring capitals. Its most persuasive musical export of the last decade has been grime – a hyperactive species of rap, born on the concrete estates of east London, characterised by jittery two-step breakbeats and practised by turns with monikers like Durrty Goodz. London’s visual artists have made smart use of the kind of muck that Zürich could not furnish. Tap “London, City of Filth” into a search engine and you’ll see some of the rich results: a pool of work by photographers who have foraged images of strange beauty from the untidy streets: a graffito that reads “ignorant, common and vulgar”; a Mondrian painting formed by a mass of torn flyposters; an empty milk trolley prone on the pavement.

The world’s cleanest cities yield no such treasures. Famously, arrest awaits those who gob a wad of gum on the pavements of Singapore. Almost as famously, when the science fiction writer William Gibson was sent there by Wired magazine in 1993, he decided that he had arrived in “Disneyland with the death penalty”. The phrase stuck – as did his criticisms. “The fuzzier brands of creativity,” Gibson noted, “are in extremely short supply.” In response, the Singaporean government banned Wired, put up banners in government buildings that read “Be Creative!” and toyed with the possibility of obliging its citizens to attend creativity classes – to be held on Saturday mornings between 10.00 and 11.30. There is, I suspect, a direct correlation to be theorised between the pristine state of Singapore’s streets and the fact that no Singaporean has ever won a Nobel Prize. Or an Oscar.

London will never sterilise itself with the regime of cultural, social and architectural DDT – but the British capital’s very success as a creative centre may be the cause of a growing and comparable problem. The destruction of a giant mass of lard beneath Leicester Square should trouble no one but the dog-owners who may unwittingly feed it to their pets for breakfast. But I would mourn the loss of London’s last unredeveloped bombsites, its last patches of unreclaimed wasteland, its last cluster of 1960s tower blocks – and I can foresee a time when I might feel obliged to lie down in front of the excavators that will transform Battersea Power Station from a glorious, guano-spotted carcass of 20th-century modernism into a brick box housing branches of Pizza Express and Yo! Sushi.

I hope that day will not come. But if London triumphs once more in TripAdvisor’s Eurovision of grime, then I will celebrate. Either by dropping a kebab at a bus stop or being sick in a doorway – I haven’t yet decided.

Monocle comment: It’s not just the grime that’s the issue with London. Transport, crime and service culture all need attention. There’s much to admire about London but it will be missing from the Monocle city list for some time yet.

Faced by a failure of civic government, many African cities rely on private firms and individuals to carry out basic services such as collecting rubbish. But, with political will, many of these problems could be solved.

The Royal Nairobi Golf Club is as exclusive as it sounds. The greens are perfectly manicured and the clubhouse does a great gin and tonic. The bankers, diplomats and politicians who play here probably feel like they are far away from the hustle and bustle of the city.

But as they stroll down the first fairway a quick glance to the right will burst their bubble. The Royal Nairobi’s next-door neighbour is Kibera, one of Africa’s largest slums, home to around one million people.

Nairobi is not the only city where the rich and poor rub shoulders so closely. One of Africa’s finest hotels, the Sheraton Addis in Ethiopia, backs onto one of the city’s worst slums. Angola’s capital, Luanda, is one the most expensive cities in the world but less than a five-minute walk from the $500-a-night hotels you’ll find Boa Vista, a ramshackle home to hundreds of thousands of Angolans that is constructed on top of a rubbish dump.

For the rich and the growing middle class, African cities can provide all the luxuries you can find in the West. There are opulent shopping malls and multi-screen cinemas, beauty spas and fine restaurants. And at the end of a long day they can drive home in an air-conditioned 4x4 to a beautiful house protected by a tall electric fence.

For those who happen to be on the outside – the vast majority – life is different. The slum, with its lack of clean water, electricity and anything provided by the government, sums up the state of African cities.

North of South Africa and south of the Sahara there simply aren’t enough cities that work. In far too many of the capitals and commercial centres across the continent basic infrastructure is non-existent – a failure by governments both local and national to provide for their people.

It is seriously damaging the continent’s economic development. When the electricity fails on a regular basis, or the internet connection is painfully slow, or it takes three hours to drive the three miles across town to a meeting, business suffers.

The failure of the state has forced individuals and companies to step in. Nairobi has dozens of small businesses that carry out activities normally associated with local government. Private companies, not the local council, collect household rubbish. Water tankers, filled from privately owned boreholes, provide richer residents with a regular supply of clean water. Young men with bags of dirt fill in potholes and then ask for change from passing motorists. One local who lived in an area with no street signs became so tired of giving directions to his house that he decided to put his own up.

There used to be no streetlights on the main roads in Nairobi. Then an enterprising businesswoman called Esther Passaris started Adopt-a-Light. Companies would pay for an advert on a lamppost – that income would pay for the upkeep of the light.

But private enterprise can go only so far. In many cases it is creating a situation where the rich are able to insulate themselves even more from the problems that the rest of a city’s residents face. And if the middle and upper classes are comfortable enough behind their electric fences there will be far less pressure on governments to provide good services for all.

“Urban leaders don’t just come out of nothing,” says Charles Landry, a leading cities expert. A strong civic leader is only likely to come from a city with a strong, politically active middle class. “A city of one million needs 10,000 who feel strongly enough to create some legitimacy.”

The lack of strong, visionary civic leaders is striking. In some African countries governments have been loath to allow such leaders to emerge, lest they create their own power base. Berhanu Nega, an opposition leader in Ethiopia, won the 2005 mayoral election in Addis Ababa. Within days he and hundreds of other opposition members were arrested on treason charges. In Madagascar, the democratically elected president Marc Ravalomanana was ousted in a coup led by Andry Rajoelina, the popular mayor of the capital, Antananarivo. Ravalomanana himself had come to power after serving as mayor.

Where they do exist, visionary leaders often lack the resources they need to do even the most basic of jobs. For the past few years Nairobi has had a town clerk, John Gakuo, who was relatively well thought of. One of his first decisions was to send out the city’s team of cleaners to sweep the streets. There was only one problem: they didn’t have any brooms, nor was there any money in the budget to buy them. Gakuo had to instruct his cleaners to pull branches off trees and fashion a broom by tying them together.

Weak judicial systems are also failing African cities. Without a strong, independent judiciary, by-laws can be ignored, tenders fiddled, environmental regulations flouted. The result is the sort of untrammelled development that has made cities such as Lagos almost unworkable.

The worst thing is that many of the problems that affect African cities and that are holding back their economic development should be relatively easy to overcome. Building proper roads and sewers, providing clean water and cheap electricity, laying the groundwork for businesses to start and thrive: none of these things are beyond the realms of possibility.

The problem is the lack of political will. None of these things can happen without leaders who are prepared to implement them. And so far, there simply aren’t enough.

Monocle comment: The pace at which African cities are growing means urban plans are always racing to keep up with the pace of migration. Seventeen of the 100 fastest-growing cities of over a million people are in Africa.

Why do some streets just seem wrong or shops leave us feeling uncomfortable? It’s all down to scale and too many planners and urbanists failing to understand its magic – or the dangers of getting it wrong.

There’s no shortage of advanced research on mankind’s assorted senses. There’s a billion-dollar industry built around creating, marketing and dispensing all kinds of smells to seduce, mask and even offend. Likewise there are other evolved industries that engineer sounds to keep our toes tapping, to keep us calm or make us bring down the house. Unfortunately, there’s very little effort or investment in understanding our sense of scale.

While there’s much talk about creating environments that are “human-scale” or developing communities that are of a “manageable scale”, more often than not these are terms used to help unwieldly developments pass box-ticking local planning authorities. Moreover, what’s marketed as small and cosy in Atlanta might be vast and alienating in Odense. It’s for this reason there should be a new global standard for human scale. The world may not need more standardisation but understanding what makes people feel comfortable in sprawling rail terminals at the crack of dawn, on bustling shopping streets during lunch hour and residential laneways past midnight could solve myriad problems for architects, developers, planners and ultimately residents.

Is it any surprise that the US retail model is failing when stores are simply too big for purpose? Or why suburban communities are crumbling when their wide roads, long driveways and impersonal high school campuses do everything to prevent human interaction rather than encourage it?

Monocle comment: The streets of Kyoto, the leafy neighbourhoods of Hamburg and the Hausmann heights of Paris all offer cues to creating cities that make humankind feel happy, included and secure.

The cities of the Ancient Greeks, with their wide, straight streets and simple grid patterns, were not just the result of a desire for order but also the offspring of necessity. A look back at the history books reveals that in those days, traffic ruled – and made cities better.

Mayors and town planners stand for order and coherent design. Deep down they dream of cutting the tape on a grand new building or street plan, commemorated in a plaque which honours their name. They dislike traffic and they warm to visions of a pedestrian future. However, they need to look backwards as well as forwards. The greatest town planners in history were the Ancient Greeks 2,000 years ago. They are a reminder to planners that traffic is not always a force for chaos. Greeks have been great expatriates throughout their history. Between 750BC and 320BC, the years from Homer to Alexander, there were as many Greeks living in towns outside Greece as in Greece itself. These towns were their new foundations and usually had a distinctive look. Wherever they went, the Greeks were quick to use straight streets, grid plans and orderly lines. In Sicily or southern Italy some of the first Greek settlements from circa 730BC onwards had a regularity which would set a modern mayor’s pulse racing with delight. They were distinct from the jumble of places such as Jericho.

In scholarly studies the Greek style of regular planning is named after an individual, Hippodamus, who was born in Greek Miletus, now on the Aegean coast of modern Turkey. He is the first planner known by name in the West and he even wrote a book on the subject. He was active at the height of the classical age, from circa 450BC onwards, and one of his most famous achievements was to lay out an orderly plan in rectangular style for Athens’s port-area, the Piraeus. Those who have to find their way round the Piraeus nowadays can only respect Hippodamus’s abandoned plan.

But Hippodamus is not responsible for inventing the regular type of town. It goes back long before him, at least to circa 550BC when we can admire it in Greek expatriate foundations, places like Metaponton in south Italy or Selinous, now Selinunte, in south-west Sicily. In none of these places can we put a name to the men who first planned the grid of straight streets or who cut the tape to declare them open.

Why did the Greeks hit on these solutions? They also invented democracy but I do not believe it was the cause of their new town planning. It only arose later. The planners had the advantage of new, vacant sites and clearly had orderly minds. They also, surely, were thinking positively of traffic – the smart processions of horses and chariots and the loaded carts pulled by mules or oxen. They moved best down straight streets, which had been kept clear for their progress. We continue to find officially inscribed Greek rules which order that streets should be kept straight and clear.

Traffic, therefore, encouraged Greek regular planning long before Hippodamus. Straight lines thus became part of a Greek’s idea of a proper city. When Alexander conquered the near east we find him personally laying out the long lines of the walls of his great Alexandria in Egypt and sitting the temples inside them. His mega-city was then grid-planned with very wide, straight streets, some with green awnings to give shade, and the city’s different quarters were named by letters of the Greek alphabet.

Similar planning was imposed on the Greek mega-city of Antioch in Syria. Jews settled in quantity in both Antioch and Alexandria and even had their own quarter in the new alphabetic plan.

In the later Roman Empire, from circa 550AD onwards, the regularity of the great Greek cities in the Near East began to break down. Many main streets became narrowed by encroaching buildings and eventually the lovely Greek grid-plans were lost under jumbled new levels. Changes in traffic were responsible. Even before the Arab armies conquered the Near East in the 630s, camels were becoming widely used as pack animals for urban loads.

The historian Richard Bulliet has even observed that after the Arab conquests there are no more known representations of loaded wheeled transport for another 700 years. He has proposed that city-dwellers voluntarily abandoned wheeled vehicles and used the camel instead, much to the profit of Arab camel-owners. Camels could pick their way through the narrow maze of streets and so the old Greek regular style was allowed to break down.

Mayors should find a moral here. If they admire orderly, straight-lined cities with long views through them, they should not wage war on motor-traffic. It is the heir of the ancient horse-drawn chariots and ox-carts and it is thanks to them that town planning first adopted a straight grid-plan, the modern mayor’s dream.

Monocle comment: Planning for cars may seem evil these days, but too many pedestrians are not always good either. Pedestrianised streets can be lifeless places.

City streets need to be pleasant places to live but also home to small businesses, craft makers and even the odd car mechanic. They might be unsightly, noisy and lower the tone of the street but they are what make a neighbourhood thrive. And anyway, too much peace and quiet can be bad for you.

Thirty years ago the house I live in was home to a printer’s. Back then lots of the buildings in my road hummed with enterprise: garages, repair shops, a taxi company. All those small-business owners have now gone and in their place have come a succession of people who have turned the old lock-ups and one-man-band premises into residences, pied-à-terres and weekday parking for CEO’s motors.

Next to my house is a recently cleared plot of land that housed the road’s last outpost of noisy business: a mechanic who believed that he was run out of town by the local council’s zealous decorating of his customers’ cars with parking tickets. Although he’d already departed before my arrival five years ago, I know this because after he shuttered his firm, he painted on the company’s gates a long detailed message in yellow paint that made his displeasure clear. Two fingers to the world in gloss.

So now our road is tranquil and the likes of Mr Repairman will never be back – it’s not just the council’s antipathy that would stymie a return but now that the road has been made so appealing, he couldn’t afford the premises to run such a modest chunk of industry.

Although in many ways I am a winner in this scrubbing up of the ’hood, something important has been lost. In a bid to please residents, roads like mine across the centre of London, and cities around the world, have unthinkingly given up important jobs, premises suitable for small-scale local employment and the life of the street. We’ve become so hooked on the value of clean service jobs and big business, that we’ve forgotten that cities also need to be places where we make things.

Of course it’s hard to persuade people that noise is needed, but a bit of clatter does us good. When streets are too quiet, every little noise becomes the sound of a potential intruder. Why is it that you can sleep with the window open on to a busy Madrid street and the sounds of late-night diners and early morning traders provide an aural comfort blanket but, in a well-mannered suburban street, just a raised voice, or even children playing, can take on a menacing echo?

There are two causes for hope on my road: one house converted by its architect owner now has his studio on the ground floor where he and his team can be glimpsed drawing and debating whenever you pass. And then there’s the pub that has weathered the years and still supplies residents and employees of the local lawyers’ offices and media firms with pints and patter. These businesses add life to the road; and, just as importantly, eyes (burglar alarms are always outperformed by attentive neighbours).

Shortly after I moved in, the road had a burst of petty crime perpetrated by a group of bored boys with time and drugs on their hands and a way with mopeds that seemed to allow them to hotwire in seconds whichever one took their fancy. Their rule was short-lived, thanks to the police, but also in part because of the pub staff who intervened, passed on sightings, and made sure the boys knew they were being observed.

But if there had been more people working in the road, I doubt that they would ever have considered it a potential base. It was the quietness that won their loyalty. And if there had still been a mechanic here, who knows, maybe he could even have found himself with a whole team of potential apprentices.

Monocle comment: We believe in small business revival that’s rooted in the community but it’s concerning how, even now, many city halls have almost given up on the role of helping support craft and are still mesmerised by the lure of corporate culture.