Tao-Rusyr Caldera

Tao-Rusyr Caldera is a stratovolcano located at the southern end of Onekotan Island, Kuril Islands, Russia. It has 7.5 km wide caldera formed during a catastrophic eruption less than 10,000 years ago (reported ages range from 5,550 to 9,400 Before Present). The waters of Kol'tsevoe Lake (, Ring Lake) fill the caldera, along with a large symmetrical andesitic cone, Krenitsyn Peak (; Japanese 黒石山; Kuroishiyama), that rises as an island within the lake. This volcano was named after Captain Pyotr Krenitsyn of the Imperial Russian Navy.