Hashima Island, often called Battleship Island because of its shape, was a densely packed coal mining facility off the coast of Nagasaki, Japan, that at its peak in the mid-20th century had one of the highest population densities ever recorded anywhere. Japan shifted away from coal toward petroleum in the 1970s, and the mine closed in 1974, the entire population left almost overnight, leaving buildings and belongings behind. it sat abandoned for decades, becoming a genuine ghost island, before eventually opening to tourists and gaining UNESCO world heritage status in 2015 as part of a set of Japanese industrial sites, a designation that's been debated given the island's wartime labor history. it also got international attention as a filming inspiration for the villain's lair in the james bond movie skyfall.
the population density stat on this place is genuinely hard to wrap your head around, apartment buildings packed insanely tight
the skyfall connection is what put it on a lot of people's radar who'd never heard of it otherwise