Stalin’s bunker
The equivalent of a 12-storey building, Stalin’s bunker – one of several – extends 37 metres (121 feet) below the ground. Built over multiple levels, with the ability to hold over 115 people for five days, it was only discovered by locals in 1991
Ulitsa Frunze, 167, Samara, Russia, +7 846 333 35 71

Stalin’s bunker, Samara | © ET1972 / Shutterstock | © ET1972 / Shutterstock