Lake Toba is a large natural lake in North Sumatra, Indonesia, occupying the caldera of a supervolcano.
Samosir, or Samosir Island, is a large volcanic island in Lake Toba, located in the north of the island of Sumatra in Indonesia. Administratively, Samosir Island is governed as six of the nine districts within Samosir Regency. The lake and island were formed after the eruption of a supervolcano some 75,000 years ago.
