The Territory of Heard Island and McDonald Islands (abbreviated as HIMI ) is an Australian external territory comprising a volcanic group of barren Antarctic islands, about two-thirds of the way from Madagascar to Antarctica. The group's overall size is 372 km2 in area and it has 101.9 km of coastline. Discovered in the mid-19th century, the islands have been an Australian territory since 1947 and contain the country's only two active volcanoes. The summit of one, Mawson Peak, is higher than any mountain on the Australian mainland. The islands lie on the Kerguelen Plateau in the Indian Ocean.
The islands are among the most remote places on Earth: They are located approximately 4099 km southwest of Perth, 3845 km southwest of Cape Leeuwin, Australia, 4200 km southeast of South Africa, 3830 km southeast of Madagascar, 1630 km north of Antarctica, and 450 km southeast of the Kerguelen Islands. The islands are currently uninhabited.