Island in the Ross Sea, Antarctica, formed by four volcanoes.

The island is sometimes taken to be part of Antarctica. Its area is 2,460 square kilometres (950 sq mi); only a small portion of the island is free of ice and snow. The planet's southernmost active volcano, Erebus (3,794 m or 12,448 ft), as well as the dormant volcano Terror (3,230 m or 10,597 ft), are situated on the island. They were named by Ross after his ships HMS Erebus and HMS Terror. The third highest elevation is Mount Bird, with Shell Glacier and Endeavour Piedmont Glacier on its slopes. Abbott Peak stands between Mount Erebus and Mount Bird. Gamble Cone stands in the east of the island.

Despite its relatively small size, Ross Island is the world's 6th highest island and has the highest average elevation of any island.