London skyscrapers that were planned but not built

London's skyline would look very different today if some of the plans for towers and skyscrapers that have been proposed in the past two centuries had gone ahead.

In 1852 there were plans for a tower in Crystal Palace that would have been the world's first skyscraper, but it was never built.

There were also plans proposed for towers along the Embankment and a monumental tower in Westminster that would have dwarfed Big Ben.

A Picture of London is on BBC Two Saturday 26 May 21:15 BST - or watch again on iPlayer.