Jökulsárlón is a large glacial lake in southeast Iceland, on the edge of Vatnajökull National Park. Situated at the head of the Breiðamerkurjökull glacier, it developed into a lake after the glacier started receding from the edge of the Atlantic Ocean. The lake has grown since then at varying rates because of melting of thec glaciers. It is now 1.5 kilometres (0.93 mi) away from the ocean’s edge and covers an area of about 18 km2 (6.9 sq mi). It recently became the deepest lake in Iceland, at over 248 metres (814 ft), as glacial retreat extended its boundaries.The size of the lake has increased fourfold since the 1970s.