From Winston Churchill to Adolf Hitler, political leaders have built bunkers to retreat to in case of emergency.

A guide illuminates part of an old elevator shaft inside "Down Street" underground station, April 13, 2016, in London. "Down Street" station in Mayfair operated between 1907 and 1932, and after closing, played an important part during the Second World War when it was transformed into the Railway Executive Committee's bomb proof shelter. During the height of the Blitz, British Prime Minister Winston Churchill took refuge in the station tunnels.
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