Lake Toba

Lake Toba fills an immense volcanic caldera in the mountains of northern Sumatra. The great island of Samosir rises from its waters, formed by the uplift of deposits laid down after an enormous eruption some 74,000 years ago. The lake and its shores are central to the homeland of the Toba Batak, whose villages occupy the surrounding highlands. Water leaves the basin through the Asahan River toward the eastern coast.