Most southerly lava lake
Mt Erebus
77.5° S decimal degree(s)
Antarctica ()

At a latitude of 77.5° S, the world's most southerly lava lake is found in the caldera of the 3,794-metre-tall (12,447-foot) Mount Erebus on Antarctica's Ross Island. The pool of lava, sometimes called Ray Lake, sits within the 500-metre-wide (1,640-foot) main crater, some 200 metres (656 feet) below the summit's rim. The lava lake itself fluctuates in size but has been estimated to generally have a surface extent diameter of 40 metres (131 feet), though the mouth of the conduit from which magma emerges is closer to 10 metres (33 feet) across. Erebus is the second highest volcano in Antarctica and the most southerly exposed active volcano, having displayed ongoing Strombolian eruptions since at least 1972, when the lava lake was first detected.

The other four permanent lava lakes are currently: Erta Ale in Ethiopia, Nyiragongo in the Democratic Republic of Congo, Kilauea in Haiwaii, USA, and Villarrica in Chile.

The world's largest lava lake is found in the crater of Mount Nyiragongo in the Democratic Republic of the Congo. It is approximately 250 m (820 ft) across and 600 m (1,970 ft) deep.

Erebus volcano's magma is a rare type called phonolite, which is up to 100 times more viscous than basalt found at Kilauea in Hawaii and Erta Ale in Ethiopia.