World Factbook
Heard Island and McDonald Islands
Territory of Heard Island and McDonald Islands
Last updated: 2026-03-28 (today)
Area
land
412 sq km
water
0 sq km
total
412 sq km
Climate
antarctic
Terrain
Heard Island - 80% ice-covered, bleak and mountainous, dominated by a large massif (Big Ben) and an active volcano (Mawson Peak); McDonald Islands - small and rocky
Land use
other
100% (2018 est.)
agricultural land
0% (2011 est.)
Location
islands in the Indian Ocean, about two-thirds of the way from Madagascar to Antarctica
Coastline
101.9 km
Elevation
lowest point
Indian Ocean 0 m
highest point
Mawson Peak on Big Ben volcano 2,745 m
Map references
Antarctic Region
Land boundaries
total
0 km
Maritime claims
territorial sea
12 nm
exclusive fishing zone
200 nm
Natural hazards
Mawson Peak, an active volcano, is on Heard Island
Geography - note
Mawson Peak on Heard Island is the highest Australian mountain; at 2,745 m (9,006 ft), Mawson is taller than Mt. Kosciuszko in mainland Australia), and one of only two active volcanoes located in Australian territory; in 1992, McDonald Island, the other active volcano, broke its dormancy and began erupting; it has erupted several times since
Natural resources
fish
Area - comparative
slightly more than two times the size of Washington, D.C.
Geographic coordinates
53 06 S, 72 31 E