Algonquin Provincial Park is a provincial park located between Georgian Bay and the Ottawa River in Ontario, Canada, mostly within the Unorganized South Part of Nipissing District. Established in 1893, it is the oldest provincial park in Canada. Additions since its creation have increased the park to its current size of about 7,653 square kilometres. The park is contiguous with several smaller, administratively separate provincial parks that protect important rivers in the area, resulting in a larger total protected area.
Its size, combined with its proximity to the major urban centres of Toronto and Ottawa, makes Algonquin one of the most popular provincial parks in the province and the country. Highway 60 runs through the south end of the park, while the Trans-Canada Highway bypasses it to the north. Over 2,400 lakes and 1,200 kilometres of streams and rivers are located within the park. Some notable examples include Canoe Lake and the Petawawa, Nipissing, Amable du Fond, Madawaska, and Tim rivers. These were formed by the retreat of the glaciers during the last ice age.
The park is considered part of the "border" between Northern Ontario and Southern Ontario.