Hiroshima, Japan 21 June 2014 The Atomic Bomb Dome, formerly known as the Hiroshima Prefectural Commercial Exhibition Hall before the bombing of the city, was the only structure left standing within the 2-kilometer radius of the hypocenter after a nuclear bomb, equivalent to 16,000 tons of TNT, exploded over Hiroshima, Japan on 6 August 1945. Referred continue reading : Atomic Bomb Dome