Lake Toba is an immense volcanic lake covering an area of 1,707 km2 (1,000 km2 bigger than Singapore) with an island in the center. Formed by a gigantic volcanic eruption some 70,000 years ago, it is probably the largest resurgent caldera on Earth.
Replace after the frenetic atmosphere of Indonesia. Swim in the volcanically warmed waters of the lake or arrange an overnight 'party' boat out on the lake if you can get enough volunteers together.
A beautiful place to do nothing at all. Plenty of second hand book shops to stock up on reading material.
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