Northern Saskatchewan is mostly covered by forest except for the Lake Athabasca Sand Dunes, the largest active sand dunes in the world north of 58°, and adjacent to the southern shore of Lake Athabasca. Southern Saskatchewan contains another area with sand dunes known as the "Great Sand Hills" covering over 300 square kilometres (120 sq mi). The Cypress Hills, located in the southwestern corner of Saskatchewan and Killdeer Badlands (Grasslands National Park), are areas of the province that were unglaciated during the last glaciation period, the Wisconsin glaciation.