Berkner Island is an Antarctic ice rise, where bedrock below sea level has caused the surrounding ice sheet to create a dome. If the ice cap were removed, the island would be underwater. Berkner Island is completely ice-covered and is about 320 kilometres (200 mi) long and 150 kilometres (93 mi) wide, with an area of 44,000 km2 (17,000 sq mi). It is surrounded by the Filchner-Ronne Ice Shelf. The northernmost point of the Berkner is about 20 kilometres (12 mi) from the open sea. It lies in the overlapping portion of the Argentine and the British Antarctic territorial claims.