A vast and varied landscape
From a great scale, Saskatchewan appears to be a quadrilateral. However, due to its size, the 49th parallel boundary and the 60th northern border appear curved. Additionally, the eastern boundary of the province is partially crooked rather than following a line of longitude, as correction lines were devised by surveyors prior to the homestead program (1880–1928). Saskatchewan is bounded on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota. Saskatchewan has the distinction of being the only Canadian province for which no borders correspond to physical geographic features. It is also one of only two provinces that are land-locked, the other being Alberta.
Saskatchewan contains two major natural regions: the Canadian Shield in the north and the Interior Plains in the south. Northern Saskatchewan is mostly covered by boreal forest except for The Lake Athabasca Sand Dunes, the largest active sand dunes in the world north of 58°, 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. The Cypress Hills, located in the southwestern corner of Saskatchewan and Killdeer Badlands (Grasslands National Park) are areas of the province that remained unglaciated during the last glaciation period. The province's highest point, 1,468m/m4,816ft is located in the Cypress Hills. The lowest point, 213m/700ft is the shore of Lake Athabasca in the far north. The province has nine distinct drainage basins made up of various rivers and watersheds draining into the Arctic Ocean, Hudson Bay, and Gulf of Mexico.
This summary courtesy Wikipedia. For more information, visit the Encyclopedia of Saskatchewan.