Urban Trawl: Croydon

The suburbs are back, this we know. Ever since Boris Johnson's 'Zone 5 Strategy' reminded everyone how successful a politician can be by appealing to the Free Born Englishman's age-old right to drive at 4 miles an hour rather than taking a bus, the Party of government has explicitly favoured suburban, south-east England, especially as the North becomes even more hostile to it. Croydon may be a typical slice of the London/Surrey grey area that has been a conservative bastion for over a century. Why is it, then, that the first impression a stranger might have of the centre is of a large, dense, multicultural, independent provincial city? Why does the London Borough of Croydon so much want to be a City itself? And what can we learn about what a 'suburb' really is from this place?

If it ever gets its long-stated wish of becoming officially 'urban', this quintessential commuter suburb will become a city of above average size, roughly the size of, say, Coventry, or Hull. It has its own rapid transport system and it's own rather particular pattern of urbanism, both of which are lacked by many official British cities. Many will be familiar with the strange sight that hits you when leaving East Croydon station – with the trams and high-rises, you could believe you were in a wealthy West German industrial city, until you walk around a little. What you find on investigation is that Croydon is in fact very English indeed, a result of the subjugation of planning to commerce. In short, what happened here in the 1960s is that an ambitious council offered businesses cheap office space if they would fund infrastructural improvements. Within an astonishingly short time, they transformed a burb into a minor metropolis of skyscrapers, underpasses and flyovers – the trams would come rather later. Since then the place has been the butt of numerous jokes. 'Mini-Manhattan', as if trying to be like New York was somehow less interesting than being like Surbiton. Croydon had, and has, ideas above its station, and for that, at least, it's hard not to warm to it. Yet the problem with the place quite quickly becomes apparent. Rather than this new metropolis being planned or coordinated, the dashing appearance from a distance gives way to a messy, chaotic reality, planned in the good old, ad hoc, throw everything in the air and see where it lands style so beloved of England.

In its ethos, the erstwhile Croydon Of The Future resembles the Enterprise Zones of the 1980s more than municipal planning, But in aesthetic, it's a 1960s living museum, because the place is remarkably intact; a mere couple of recladdings, only two completed post-1970s towers (neither of the slightest note, though Foster and Make schemes are planned). Much of what you can see is mosaic, concrete and glass in the English corporate modernist manner. Accordingly, it has an accidental uniqueness – things obliterated elsewhere survive. There's a fair amount of period charm, not much in terms of real quality. Seifert's fabulous NLA Tower, probably their best along with Centre Point and NatWest, is justifiably Mini-Manhattan's Empire State; but there's little else that shows any spark. The pleasure instead is seeing the past's generic, everyday architecture in an unusual state of completeness and survival.

So there's the once-chic, now-shabby tapering tower the council built as their own offices, which complements nicely their earlier, enjoyably debased Victorian halls; a couple of sub-Seifert cubist experiments; a jollily Festival of Britain Travelodge; Hilberseimer-style Zeilenbau blocks step along where a developer could get a big enough plot; and the chimneys of a power station ornament a giant IKEA. Residential towers are massively outnumbered, but there's three worth noting: the Lubetkinesque Cromwell Tower, some more Festival styling on Coombe Road, or the cute Zodiac House, which fans of the sitcom Peep Show will be familiar with. The best bit, comfortingly, is an enclave of public space, the mosaic-piloti and shell roof Arcade of St George's Walk, which emerges from behind the drab Nestle Tower.

The problem, or for the dedicated flâneur, the fun, is in how it interacts with the suburb all around. Or how it doesn't. Arrangements are totally random – a row of artisans' terraces with skyscrapers behind, would-be secluded Tudorbethan facing giant high-rises, the sound of birdsong accompanying an endless rumble of traffic. Sometimes the place seems to be mocking itself, as when churchyard meets concrete subway you find the sign 'OLD TOWN CONSERVATION AREA'. In fact, there's a lot of pre-Victorian, never mind pre-1960s remnants in among the towers, if you know where to find them. It adds up to one of London's more surreal urban experiences, taking the capital's pre-existing aptitude for the juxtaposition and amplifying it.

So Croydon is, at first, nothing like what a suburb is supposed to be. But look for the housing built at the same time as the new metropolis and you find that LA was the model much more than Hamburg or Chicago. Wates' Park Hill estate (no relation) is a case in point. This is one of the leafiest, lushest of suburbs, with either bland, tiny detached houses or vaguely Eric Lyons terraces in amongst mature trees giving way to, extraordinarily, three short terraces by Atelier 5, in a state of impeccable kemptness. However, this is exceptional; what is much more typical is the sprawl around the Borough's centre, those burbs where 'going into town' means going into Croydon, not the West End.

Thornton Heath, for instance, where the borough's only notable post-1970s building has just been completed, FAT's new Library extension. Drop the 'OMG jokes' reaction for a second (if we're lucky, the architects might sometime do the same), and it's a remarkably serious, not at all whimsical public building, warm, welcoming and on this Tuesday afternoon, very well used. It looks comfortable, which is an interestingly rare thing in new architecture. As a building, it's a great reproach to the rash of library closures. It takes a small-scale thing and makes it better. But this is a place with large-scale problems. And far more typical of the attempts to solve it are new spec blocks of flats, or Saunders Architects' generic Blairbuild Thornton Heath Leisure Centre. Maybe that'll survive long enough to acquire the centre's unexpected period charm, but it seems unlikely. This place has suffered from over a century of non-plan, and the result is chaos – dereliction next to newbuild, dramatically crammed and then almost criminally low-density. It's full of surprises for the walker, but it's a disastrous way to run a city, as the horrendous traffic, or the decidedly fractious tenor of public interaction, makes very clear.

But what does it say about South-East, suburban England, the area that lords it over the rest of the country? This place is, in theory, a major centre of our most powerful, most wealthy, most leafy area. You'd never guess, though, as it feels like another Britain entirely - a poor but multiracial, intriguing but miserable place which could really do with social planning and social housing, rather than more speculation and a BID. Croydon is not smug; unlike neighbours such as Carshalton, it won't be going all creeping Jesus Big Society anytime soon. It's a place. It could be much more so.