Gunkanjima, or Battleship Island, flourished as a coal mine from 1870, when coal was discovered in the late Edo period, until it closed in 1974. Many historic buildings remain on the island, and it has been registered as a World Heritage Site as part of the "Sites of Japan's Meiji Industrial Revolution." One of the most famous buildings is Japan's first high-rise apartment made of reinforced concrete. While visitors cannot enter the interior, just seeing the exterior, which has decayed over time, is impressive.
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