Tao-Rusyr Caldera (Russian: Тао-Русыр) 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 5550 to 9400 Before Present). The waters of Kal'tsevoe Lake fill the caldera, along with a large symmetrical andesitic cone, Krenitsyn Peak, that rises as an island within the lake.