A disused Tube station where Winston Churchill took refuge during the Blitz is among several London Underground sites to be opened to the public.
Down Street in Mayfair, a station from 1907 to 1932, was used as a bomb-proof bunker for the prime minister during World War Two.
Passageways under Euston Station and Clapham South's deep-level bomb shelter will also be made accessible.
Tours of the sites will be run by London Transport Museum.
Down Street was also used as the main location for coordinating the country's railways.
Tours will also take place in the warren of tunnels 180 steps beneath Clapham South.
The site was used as a shelter during the Blitz, as a base for Caribbean migrants arriving in 1948, and even by visitors to the Festival of Britain in 1951.
London Underground's former headquarters at 55 Broadway near St James' Park, which opened in 1929, will be another site featured in the Hidden London project.
Chris Nix of London Transport Museum said visitors would get "a rare opportunity to see a secret side of London".
Tickets for the tours, which will begin next month, go on sale on 20 April.