Jökulsárlón (; literally "glacial river lagoon") 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 the glaciers. It is now away from the ocean's edge and covers an area of about . It recently became the deepest lake in Iceland, at over , as glacial retreat extended its boundaries. The size of the lake has increased fourfold since the 1970s. It is considered as one of the natural wonders of Iceland.