Which volcano is the highest mountain in Java, Indonesia, at about 3,676 metres?

Mount Semeru is the highest mountain in Java, Indonesia, at about 3,676 metres.

Also called Mahameru, meaning Great Mountain, Semeru rises in East Java and forms part of the Bromo Tengger Semeru volcanic complex. Its summit, Mahameru, is frequently active and can produce ash plumes, explosions, and lava-related hazards.

Semeru is one of Indonesia's most active volcanoes. Its activity has repeatedly affected nearby communities, especially through ashfall and pyroclastic flows. The volcano's steep slopes and tropical environment can also create lahars when loose volcanic material is remobilized by heavy rain.

Mount Semeru is not the same as Mount Merapi, which is Indonesia's most active volcano and lies on Java near Yogyakarta. Semeru's distinction is its elevation: it is Java's highest point, while Merapi is better known for its frequent dome-collapse activity and major hazards.