The geography of Indonesia is dominated by volcanoes that are formed due to subduction zones between the Eurasian plate and the Indo-Australian plate. Some of the volcanoes are notable for their eruptions, for instance, Krakatau for its global effects in 1883, Lake Toba for its supervolcanic eruption estimated to have occurred 74,000 Before Present which was responsible for six years of volcanic winter, and Mount Tambora for the most violent eruption in recorded history in 1815.
Lake Ranau (Danau Ranau) is a lake in the province of Lampung, southern Sumatra in Indonesia. It is the second largest lake on the island of Sumatra. The lake is created by a large earthquake and a volcanic eruption that caused a large lag in the area.
Geographically seen, Lake Ranau is a hilly area with valleys which comes with a typical cool climate. This makes it a tourist destination mainly for local and regional tourists. Fishers report catching various types of fish in the lake as well.
In the center of the lake is a small island, known as Marisa Island. On that island is a hot water source that is now commercially exploited, especially after it was designated a tourist destination by the regional government in 2007. There are even several homestays that target regional tourists now.