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.
Mount Lokon, together with Mount Empung, is a twin volcano (2.2 kilometer apart) in the northern Sulawesi, Indonesia, roughly 10 kilometer south of Manado. Both rise above the Tondano plain and are among active volcanoes of Sulawesi. Mount Lokon has a flat and craterless top.
Lokon formed during a period of andesitic volcanism on ring fractures resulting from the Tondano caldera's early to mid-Pleistocene collapse. Recently-erupted material remains andesitic in composition and consists of ash plumes and, less commonly, pyroclastic flows and lava domes.
The volcano erupted on 15 July 2011, forcing thousands of people to evacuate. The last major eruption of Mount Lokon before in 1991, killed a Swiss hiker and forced thousands of people to flee their homes.