Peter I Island is an isolated, mainly snow covered island, 11 miles long and 5 miles wide, located 200 miles NE of Cape Braathen, Thurston Island. The island is lofty with steep slopes, attaining a height of 1,755 m in Lars Christensen Peak. Discovered in January 1821 by Capt. Thaddeus Bellingshausen, who named it for Peter the Great of Russia.