The French River (or Rivière des Français) is a river in central Ontario, Canada. It flows 110 kilometres from Lake Nipissing west to Georgian Bay. The river largely follows the boundary between the Parry Sound District and the Sudbury District, and in most contexts is considered the dividing line between Northern Ontario and Southern Ontario.
The French River flows through typical Canadian Shield country, in many places exposing rugged glaciated rock but also through heavily forested areas on the upper portion. The mouth of the river forms an extensive delta, containing countless islands and numerous channels which vary from narrow, enclosed steep-walled gorges, falls and rapids, to broad expanses of open water.
Tributaries of this river include the:
It was used as a transportation corridor by the Algonquian peoples of this region. The Ojibwa named this the "French River" because it became associated with French explorers of the 17th century, including Étienne Brûlé, Samuel de Champlain and Pierre-Esprit Radisson, and missionaries.
Together with the Ottawa and Mattawa Rivers, the French River formed part of the water highway from Montreal to Lake Superior in the days of the fur trade. It remained a major canoe route until about 1820. It was later settled as a summer tourist and recreation area. For this reason, the French River was designated a Canadian Heritage River in 1986.
Near the end of the 19th century, logging became the primary activity in the area. Because of the rugged nature of the Canadian Shield country surrounding this river, large parts of this river remain relatively untouched and it is now a popular location for recreational canoeing, kayaking, fishing and boating.