St Paul's at risk of being rubbed out of the London skyline forever with nearly 250 high rise developments planned for the capital

Study identifies 236 planned high-rise towers of more than 20 storeys

77 per cent are intended for the city's central and eastern districts

'We need to understand what the impact is,' says thinktank director



At 365ft high, St Paul's Cathedral dominated central London's skyline for almost 300 years, until the development of Canary Wharf and, later, the Gherkin and the Shard.

And now Sir Christopher Wren's famous dome risks being obscured entirely, with almost 250 skyscrapers proposed, approved or already under construction in the capital.

An architectural thinktank has identified 236 buildings of more than 20 storeys that could be on the way, four fifths of them intended as high-rise blocks of flats.

Under threat: Iconic symbol of London St Paul's Cathedral could be blotted out of the skyline by hundreds of planned skyscrapers

London's changing skyline: A computer generated image shows how the Square Mile financial district will look when its new towers have been built. 236 high-rise developments are planned for the capital

A further 18 will be offices, eight will be hotels, 13 are mixed use, and one is to be an educational institute, according to New London Architecture.

Nearly half have already been approved and about a fifth are now being built, according to a study by the think tank based on local authority figures, which has been seen by The Guardian.

And they are set to drastically reshape the London skyline, with 33 of them between 40 and 49 floors, and 22 with 50 or more.

The building boom is concentrated in London's centre and its hitherto dilapidated east, which together account for 77 per cent of the new skyscrapers.

Tower Hamlets, Lambeth, Greenwich, Newham and Southwark will between them have 140 of the 236 towers.

Blackfriars Bridge, circa 1900: At 365ft high, St Paul's Cathedral was London's tallest building from 1710 to 1962

The survey was prompted by London Mayor Boris Johnson who, as he announced his revised housing strategy last year, vowed that it wouldn't mean towers 'popping up all over London,' said NLA director Peter Murray.

But, Mr Murray said, after looking at the planning data from various boroughs, his researchers had found that it would actually mean exactly that.

'Just like in the 1960s, when we had to build a whole lot of houses, we are going to go higher than I think a lot of people in London had imagined,' he told The Guardian.

He added: 'I've got nothing against towers at all, but we need to understand what the impact is.'

Shape of things to come: Canary Wharf in London's Docklands. The building boom is concentrated in London's centre and east, which together account for 77 per cent of the new skyscrapers

The pressure to build upwards is coming from demands on the Greater London Assembly and local authorities to come up with more housing at a time of very high land prices.

Foreign investors from east Asia, who are buying into London property in unprecedented numbers, are also having an effect as they are comfortable with tall buildings which have long been part of the urban landscape in that region.

The Mayor's office is trying to strike a balance between protection of the city's historic skyline and the need to house a million more people and create half-a-million new jobs, said sir Edward Lister, deputy mayor for planning.