WLake 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 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.
WAsahan River is one of the principal rivers in North Sumatra, Indonesia, that begins in Porsea, Toba Samosir Regency at the Southeast part of Lake Toba.
WLake Sidihoni is a lake located within Samosir Island which itself is an island within Lake Toba, in North Sumatra, Indonesia and is therefore notable for being a "lake on an island in a lake on an island". It is approximately 11–12 km to the east of hot spring pools at Pangururan.
WParapat is a small town in North Sumatra province on the edge of Lake Toba, on the Uluan Peninsula where it forms the narrowest eastern link to Samosir Island. It is the primary transit point by ferry for visitors going to Samosir Island, and connected via Trans-Sumatran Highway to Pematang Siantar by a 48 km road. Administratively it is part of Simalungun Regency.
WFor the Regency named Samosir, see Samosir Regency.
WMV Sinar Bangun sank on 18 June 2018 in Lake Toba, North Sumatra, Indonesia, during its trip from Simanindo Harbour in Samosir Island to Tiga Ras Harbour in Simalungun Regency. The ferry was carrying 188 passengers and crew. After the sinking, authorities immediately deployed search and rescue personnel to the area. Twenty-one survivors were rescued, three bodies were found and 164 people were listed as missing and presumed dead.
WThe Youngest Toba eruption was a supervolcanic eruption that occurred around 75,000 years ago at the site of present-day Lake Toba in Sumatra, Indonesia. It is one of the Earth's largest known explosive eruptions. The Toba catastrophe theory holds that this event caused a global volcanic winter of six to ten years and possibly a 1,000-year-long cooling episode.