Aogashima, The Inhabited Volcanic Island of Japan

Aogashima is a tropical volcanic island in the Philippine Sea, administered by Tokyo despite being located approximately 358 kilometres (222 mi) south of Tokyo. It is the southernmost and most isolated inhabited island of the Izu archipelago.

Aogashima is a volcanic island 3.5 km in length with a maximum width of 2.5 km, formed by the overlapping remnants of at least four submarine calderas. The island is surrounded by very steep rugged cliffs of layered volcanic deposits. The southern coast also rises to a sharp ridge forming one edge of a caldera named Ikenosawa with a diameter of 1.5 km. The caldera dominates the island, with one point on its southern ridge, Otonbu with a height of 423 metres (1,388 ft), as the island’s highest point. The caldera is occupied by a secondary cone named Maruyama.

It is still considered a Class-C active volcano by the Japan Meteorological Agency though it last erupted in the 1780′s.  The 1781-1785 eruptions led to mass evactuation in 1783 and then severe casualties in 1785 – over 1/3 of the population. The only way to reach the island is either through Sanbō port on a small ship during calm seas or chartered helicopter.