Lake Toba

Lake Toba is a volcanic lake with a length of 100 kilometers and 30 kilometers wide, located in North Sumatra Province, Indonesia. This lake is the largest lake in Indonesia and Southeast Asia. In the middle of this lake there is a volcanic island called Pulau Samosir.

Lake Toba has long become an important tourist destination in North Sumatra in addition to Bukit Lawang and Nias, attract domestic and foreign tourists.

It is estimated that Lake Toba explosion occurred at about 73000-75000 years ago and an eruption Supervolcano (super volcano) the most recent.

After the eruption, the caldera formed which is then filled with water and became what is now known as Lake Toba. Pressure upward by magma that has not come out cause the emergence of Samosir Island.

source : http://id.wikipedia.org/wiki/Danau_Toba