Saskatchewan is a prairie and boreal province in western Canada, the only province without a natural border. It has an area of 651,900 square kilometres (251,700 sq mi), nearly 10 percent of which (59,366 square kilometres (22,900 sq mi)) is fresh water, composed mostly of rivers, reservoirs, and the province's 100,000 lakes. Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on the south by the U.S. states of Montana and North Dakota. As of late 2018, Saskatchewan's population was estimated at 1,165,903. Regina is the capital.