A tower above Selfridge’s department store, Oxford Street
A tower above Selfridge’s department store, Oxford Street - Nine years after the store opened, this design was drawn up for Gordon Selfridge by architect Philip Tilden in 1918. No one knows why it was designed – whether out of fancy or the grand ambition of the flamboyant Selfridge

From Nelson’s Globe to a tower that dwarfs Big Ben and a landing strip on Park Lane, here are 300 years of designs for London that, if built, would have changed the city for ever