Barren Island is an island located in the Andaman Sea. It is the only confirmed active volcano in the Indian subcontinent, and the only active volcano along a chain of volcanoes from Sumatra to Myanmar. It is a part of the Indian Union territory of Andaman and Nicobar Islands, and lies about 138 km (86 mi) northeast of the territory's capital, Port Blair.

The Andaman Sea is a marginal sea of the northeastern Indian Ocean bounded by the coastlines of Myanmar and Thailand along the Gulf of Martaban and the west side of the Malay Peninsula, and separated from the Bay of Bengal to its west by the Andaman Islands and the Nicobar Islands. Its southern end is at Breueh Island just north of Sumatra, with the Strait of Malacca further southeast.