Tongkoko (also spelled Tankoko) is a stratovolcano 8 km north of the city of Bitung in NE Sulawesi, the most northeasterly of the volcanoes on the Island of Sulawesi, before the chain extends into the ocean as a chain of island volcanoes.
Tangkoko volcano is mostly known for its location within Tangkoko-Batuangas Dua Saudara National Park, home to tarsiers, a small primate with large eyes and active at night (nocturnal).