Mount Erebus in Antarctica is a volcano on Earth, the second highest volcano in Antarctica (after Mount Sidley), and the 6th highest ultra mountain on an island. With a summit elevation of 3,794 metres (12,448 ft), it is located on Ross Island, which is also home to three inactive volcanoes, notably Mount Terror. Mount Erebus is part of the Pacific Ring of Fire, which includes over 160 active volcanoes.

The volcano has been observed to be continuously active since 1972 and is the site of the Mount Erebus Volcano Observatory run by the New Mexico Institute of Mining and Technology.