Lake Toba (Indonesian: Danau Toba) is a large natural lake in North Sumatra, Indonesia, occupying the caldera of a supervolcano. The lake is located in the middle of the northern part of the island of Sumatra, with a surface elevation of about 900 metres (2,953 ft), the lake stretches from 2.88°N 98.52°E to 2.35°N 99.1°E.
The lake is about 100 kilometres (62 miles) long, 30 kilometres (19 mi) wide, and up to 505 metres (1,657 ft) deep.
It is the largest lake in Indonesia and the largest volcanic lake in the world. Lake Toba Caldera is one of the twenty Geoparks in Indonesia, which is recognised in July 2020 as one of the UNESCO Global Geopark.
Lake Toba is the site of a supervolcanic eruption estimated at VEI 8 that occurred 69,000 to 77,000 years ago, representing a climate-changing event. Recent advances in dating methods suggest a more accurate identification of 74,000 years ago as the date. It is the largest-known explosive eruption on Earth in the last 25 million years.
According to en.wikipedia