Mount Dempo is a high stratovolcano

Stratovolcano

A stratovolcano, also known as a composite volcano, is a tall, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions...

 that rises above Pasumah Plain in the province of South Sumatra

South Sumatra

South Sumatra is a province of Indonesia.-Geography:It is on the island of Sumatra, and borders the provinces of Lampung to the south, Bengkulu to the west, and Jambi to the north...

 in Sumatra

Sumatra

Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...

, Indonesia

Indonesia

Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

. Seven crater

Volcanic crater

A volcanic crater is a circular depression in the ground caused by volcanic activity. It is typically a basin, circular in form within which occurs a vent from which magma erupts as gases, lava, and ejecta. A crater can be of large dimensions, and sometimes of great depth...

s are found around the summit. A 400 m wide lake is found at the northwest end of the crater complex.

The most recent activity has been in 2009. Historical activity has been confined to being small-to-moderate explosive activity that produced ashfall near the volcano.