Athabasca Sand Dunes Provincial Park, Provincial park on the south shore of Lake Athabasca, Saskatchewan, Canada

Athabasca Sand Dunes Provincial Park stretches 100 kilometres along the southern shore of Lake Athabasca in northern Saskatchewan. Its parabolic dunes, 400 to 1,500 metres long and up to 30 metres high, lie on the Athabasca Basin of the Canadian Shield. The William River crosses the western section and ends in a large delta; the McFarlane River runs through the far east.

The dunes date to about 8,000 years ago, at the end of the last glacial period. Meltwater carried sand, silt and sediment from local sandstone into Lake Athabasca, then much higher; as the lake fell to its modern level, the deposits were exposed. The idea of protection dates from 1969, and the provincial wilderness park was established on August 24, 1992.

The park wraps around the Fond du Lac 231 Indian reserve on the McFarlane River, and the First Nations village of Fond du Lac lies about 44 kilometres by air from the park's eastern boundary. The dunes lie in the Northern Saskatchewan Administration District, far northwest of the province.

The park is only accessible by float plane or boat, and there are no permanent facilities or services within the area. Visitors should prepare for a remote and self-sufficient experience.

The dunes sit above an enormous aquifer: groundwater lies beneath the whole sandy region, including the ground south of the dunes, and it sustains the plant life and shapes how the dunes develop. The bedrock of sandstone lies only about 20 metres below the surface.