Ottawa River

The Ottawa River (rivière des Outaouais) is a Canadian river which for most of its length defines the border between the provinces of Ontario and Quebec. It rises in northern Ontario and tumbles over the Chaudière Falls at Ottawa where it further takes in the Rideau River and Gatineau River. Between the Chaudière Falls and Rideau Falls lies Parliament Hill perched atop a steep and militarily strategic gorge. The Ottawa River drains into the Saint Lawrence River at Montreal, forming Lac Saint-Louis. In the early 19th century, the Ottawa River was also connected to Lake Ontario via construction of the Rideau Canal.