Secret cabinet and bomb shelters: Inside London Underground's ghost stations

LONDON, United Kingdom — Between two platforms of the Picadilly Circus station, Siddy Holloway takes her visitors through a passage to a forgotten London.

The London Transport Museum organizes tours in the abandoned stations of the world's oldest underground railway to discover its secrets.

"Picadilly Circus being Picadilly Circus, sort of the heart of London, was actually one of the frequently used tube shelters during the Blitz and then later on the V-weapon attacks. Up to 7000 people would shelter in this station per night," Siddy Holloway, guide pour London Hidden Tour said.