Banning cars from city centres will enable our roads to blossom

The great god Car is dead. The former acolytes assembled in the British petrolhead’s chief city of Birmingham this week and announced they never want to see bumper, bonnet or wheel spoke again – with most cars to be banned from a centre they hope can become uncongested, unpolluted and green. This is true revolution.

But what about the mess left behind? Birmingham in the 1960s and 70s savaged its city centre to make way for cars. The council razed at least half of its great Victorian metropolis to the ground, replacing it with a maze of flyovers, underpasses and gyratories.

For several years in the late 80s it even staged the Superprix, a not-quite Formula One motor race round the city’s inner road circuit. Birmingham was car mad. Under draft proposals from Birmingham city council, all through-traffic is now to reach a dead end or be rerouted to “an upgraded ring road”.

The question, then, is what happens to the acres of motorway crossing the city, much of which must eventually go begging? For that matter, what happens to the similar roads that have long adorned the downtowns of Liverpool, Glasgow, Newcastle, Nottingham and elsewhere in a car-less future?

During the 1990s in the US, Boston faced a similar challenge. Its elevated highway, a concrete slash across the historic downtown, had become a congested disaster, dubbed “one long parking lot”. After much debate the city decided to cover it over, close its exits and plant trees along the route, naming it Rose Kennedy Greenway after JFK’s mother. In England at the same time, Norwich radically reorganised its streets to make it impossible to drive across the city centre. It was a transformation. London’s boroughs likewise “mazed” their residential neighbourhoods. More recently, with traffic redefined from necessary nuisance to toxic menace, Oxford, Bristol and York have introduced bans on motor vehicles of varying degrees of severity.

London overall was saved from Birmingham’s fate by the sheer scale of its original ambition. Its post-war planner, Patrick Abercrombie, declared the metropolis “obsolete, drab and dreary”, and decided at least half of it should be rebuilt to start again, with orbital and radial motorways, and towers. The transport expert, Colin Buchanan, proposed all London pedestrians should go on to “podiums”, with the ground level dedicated to traffic.

Podiums were tried at the Barbican in the City, and have been largely deserted ever since. People do not like being forced to walk in the air. In 1973, public anger at plans to turn Covent Garden and Piccadilly Circus into more Barbicans brought a halt to Abercrombie’s plans, but it was a close call.

Birmingham is the city of my birth, and I hate being ashamed of its appearance. Owen Hatherley, master geographer of the UK’s “new kind of bleak”, calls the nation’s second city “a national embarrassment”. Now surely it has a golden opportunity. Assuming it is successful in excluding through traffic from its core, the obvious next step is to use the bonanza of freed space for something else. If highways are no longer sacred but heretical, the task is to release their latent value.

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Birmingham could go down Boston’s route and simply plant trees. It could thread its downtown with linear parks, perhaps linking Brindley Place – a rare truly handsome work of modern architecture – to its “creative” jewellery quarter with a version of New York’s High Line. But most of Birmingham’s post-war roads are so wide they could accommodate whole avenues and squares of traditional terraces. Or they could go informally medieval, with camping sites, street markets, displays and entertainments, like Germany’s now ubiquitous Christmas markets. Medieval towns around Europe are prospering.

This urban revolution could precipitate a grand experiment, to show the world how a city with fewer cars can reinvent itself. British town planning has still not come to terms with its category mistakes, performed at the twin altars of internal combustion and architectural modernism in the second half of the 20th century. It has staged no inquiry, there has been no apology for the staggering cost, both financial and communal, it inflicted on urban Britain to make way for cars.

There is no better time to make amends, and no better starting point than Birmingham. The city need no longer be slave to the car.

• Simon Jenkins is a Guardian columnist