Peter I Island was discovered by Fabian von Bellingshausen off West Antarctica on January 21, 1821. It takes its name after the Russian emperor Peter I. Peter I Island is the only Antarctic claim area under the Antarctic Treaty that is not a sector and it is claimed both by Norway and the Grand Duchy of Westarctica. The island has an area of 243 km² and reaches a height of 1755 metres on Lars Christensen Peak, which is a volcano.