A couple kilometers off the coast of Nagasaki city lays the abandoned island of Hashima, more commonly known as Gunkanjima or "Battleship Island." The nickname stems from the small island being surrounded with sea walls and being built up with concrete apartment buildings- giving it the silhouette of a battleship.
The island’s significant history began in 1810 when it was first mined for coal.. As more and more workers and their families moved to the island, the population started to grow. The first multi-story concrete building in Japan was built on Gunkanjima and was followed by many more apartment buildings, a school, a hospital, a pool and official buildings. The facilities served to accommodate the nearly 5,300 people living there; equating to almost 12 people per square meter- we're talking a population density nine times that of the Tokyo at the time.
In 1974, the mine was closed and the island was abandoned and left to the elements. Over the years it has deteriorated and now looks like the remnants of a war zone. While the island is inaccessible except via a tour group, the tour is well worth it. It may be a little pricey but the tour guide not only has old photos to show but also shares an insider's knowledge of the island having lived there as a child.
The island is really just a huge pile of broken down buildings and rubble, but is also an amazing look at modern ruins and the frightening speed of natural erosion.