Barbie's birthday

Architecture - Lilian Pizzichini on a living model of 1950s kitsch and freakery

The Barbican in London is celebrating its 20th anniversary as "the country's only fully integrated arts centre". The exhibition "Barbican: this was tomorrow", which marks the occasion, traces the development of an attempt to create compact urban lifestyles in the City of London. As a result, we are asked to do many things. First (sadly, the irony is lost on the exhibitors) we are asked to find the exhibition.

Once you have located it (The Curve, Level One), allow yourself to be taken back in time to postwar London. Five black-and-white photographs remind us what it was like to be poor, working-class city dwellers. "Slum" is the bald title of the first, which shows washing hanging from a line in a terraced yard and the open door to an outside privy. The two-up two-down that houses the people who wear the clothes that hang on the line in the yard is crumbling and old. Weeds curl round bricks, wood is rotting. Yes, you think, this is probably unhealthy. Yes, you infer, old equals bad.

The second image is sternly titled "Muddled use of land". It is an aerial shot of arterial roads intersecting the city along the lines set by the 19th-century canals and railway tracks, which themselves mimicked the old commercial routes that brought fresh produce into the city. There is movement, admittedly of a commercial kind, but the picture breathes with possibilities. "Lack of open space" is sterner still. We see a cobbled road, braced by terraced houses, on which children are playing skipping games and riding tricycles and women are congregating for a chat. I wonder if any of them are the inhabitants of the slum we have already visited. Strangely, they seem to be enjoying what muddled open space they have. But there is no time to conjecture, because next we have "The traffic problem", which shows an orderly queue of double-decker buses and vintage cars waiting for the traffic lights to change.

It is the last image, however, that is the most unintentionally ironic. "Architectural Squalor" shows Piccadilly Circus in all its pristine glory - white Carrara marble and gleaming Portland stone offset with neon signs advertising Bovril and Schweppes. Eros has never looked perkier.

It was the pipe-smoking, cardigan-wearing, social-democratic town planners and architects who decided that postwar London needed "a general tidying-up". The intricate network of streets, canals and railway routes got in the way of churches, warehouses, parks and docks. Efficiency was the keyword, and "people must be separated from traffic". Thus we have the Barbican's notoriously unnavigable podium walkways. This was the way to deal with an increasingly congested modern city, they decided.

The Barbican complex sprawls in an eastward direction just north of St Paul's Cathedral, across 60 acres of the City of London. Three tower blocks dominate a loose conglomeration of slab buildings. The towers are 125 metres high, and at the planning stage were the tallest residential buildings in Europe and the only high-density housing available. The 2,113 flats are home to about 6,500 people.

Give expression to structure rather than conceal it - allude to Frank Lloyd Wright's triangular towers - in order to create a "genuine residential neighbourhood". That's the idea, anyway. In design terms, the Barbican was conceived as a concrete mix of Renaissance Italy, spartan Stockholm and a sophisticatedly stark Corbusier villa. The formal gardens were created to evoke 16th-century Italian and French courtyards. The Arts Centre itself was designed as a container that would hold separate performance buildings. The centre was built between 1963 and 1982 at a cost of about £500m in today's money. Last September, it was made a Grade II listed building.

It cannot be argued that postwar architects and town planners did not have the best of intentions and, in the wake of the Luftwaffe and doodlebugs, the best of opportunities to see them materialised. More than 100,000 houses had been destroyed in London, and another million needed war-damage repairs. At the same time, there was a dramatic increase in demand for housing due to demobilisation and the postwar baby boom.

"There mustn't be any overcrowding," admonishes the architect Sir Patrick Abercrombie in the looped video on display in the Curve. In the old days, he exclaims in between puffs on his pipe, "there was no planning at all", and yet the "people must be separated from traffic". So there will be no crossings in the new traffic systems, he goes on to say, only tunnels and subways that would effectively separate local and national traffic. Perhaps he means something approaching the horrifically drab and vaguely menacing Beech Street, one of the covered roads that lead to the Barbican and in effect cut it off from the lifeblood - the people, for pity's sake - of the city.

If the architects were possessed of a social-democratic vision, the Corporation of London had more pragmatic concerns. Its leaders decided that only a certain type of person could be housed under their aegis. In order to retain their political autonomy, they needed a reliable electorate capable of paying high rents which, in turn, would make the whole skyscraping caboodle economically justifiable. Hence the proliferation of one-bedroomed flats designed to high specifications for the discerning, cocktail-quaffing professional. Today, they are a living model of Fifties kitsch and design freakery.

By the early 1960s, the Corporation had decided to develop an arts complex of national significance which, the exhibition claims, "was to expand the artistic centre of London eastwards". Anyone who lives in east London would laugh at this idea. The planners of the Barbican in effect divorced it from the rest of the city at the drawing board. There is no exchange of cultural juices. The only reason the arts have flourished east of Aldgate is because the rents are cheap. Besides, culture cannot be contained in a defensive tower, even if there are three of them and they are 45 storeys high.

Finally, the Curve comes round to its last looped video. This one shows residents of the Barbican singing its praises. They are two artists and an arts curator. They are very much a part of what they call the "design community". They love the space: it is calming, they say. Piers Gough, an architect, explains that it would be a very great loss to go back to streets and houses with pavements and gardens either side. But then he's an architect, isn't he? No wonder he loves the Barbican - designed as it is to within an inch of its life.

Last up on the vid are Katharine Rumens, the Rector of St Giles, Cripplegate, the ancient church that stands forlorn amid the concrete, woodwork and rustic brick, and Iain Sinclair, the writer and unofficial historian of London. No one knows where her church is, says the Rector, within this "corridor of shut doors" - although, she does concede, she is slowly finding a sense of belonging among her parishioners. But it is Sinclair who deserves the last word, and it is this: at first, he felt resentful at routes being imposed upon him. Then, he found a measure of silence and contemplation, a small city within itself. Yet he finds himself asking: where are the people?

Lilian Pizzichini's Dead Men's Wages is published by Picador (£15.99)