Gunkanjima, meaning “battleship island” in Japanese, is the nickname of several islands Hashima Island (Japanese Hashima), Nagasaki Prefecture,

Gunkanjima is a small island located about 20 kilometers from Nagasaki Port. Until 1974, the island served as a coal mine,

Gunkanjima Island in Nagasaki, Japan: Once the most densely populated place in the world, this island is now a ghost town.

AloJapan.com