Gilbert Scott was not the obvious choice of architect, but the 22-year-old Roman Catholic won the design competition and began the enormous task of creating the austere, brooding building.

As Kevin clambers over Liverpool Cathedral’s vast gothic arches - the highest ever built - and discovers the medieval working methods that were used to construct the 20th century cathedral. He also looks at the fortunes of the city during the century. The project was intended to show that Liverpool could outdo the great medieval cities but by the time it was fmished, the wealth had disappeared

Episode 6

How does a vertical slum become an icon of urban cool? Kevin McCloud finds out as he climbs Erno Goldfinger’s Trellick Tower, in London.

The 322-foot high concrete council tower block was built in an age of 1960s optimism, but the high rise culture was already out of favour by the time it was completed. The building quickly became a nightmare for residents, faced with drug abuse and crime on their doorsteps. But now it’s listed by English Heritage and flats are selling for around £200,000.

Kevin climbs the concrete ‘cliff-face’ of Trellick Tower in a bid to understand why the building is now featured on the trendiest t-shirts. He clambers over the balconies and talks to residents who have seen the tower change from junkie-ridden high rise to the ultimate desirable address for the style slaves. The building was a vast undertaking for the then Greater London Council - but Kevin finds out how compromises and cost-cutting marred Goldfinger’s vision of a community in the sky.

Related Links:

- The future of architecture in London, Paris and New York

- Megabuilders: The world's biggest projects

- Save the city simulation game

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