The river flows north from Upper Rideau Lake and empties into the Ottawa River at the Rideau Falls in Ottawa, Ontario.

[1] The Rideau Canal, which allows travel from Ottawa to the city of Kingston, Ontario on Lake Ontario, was formed by joining the Rideau River with the Cataraqui River.

The river diverges from the Canal at Hog's Back Falls in Ottawa.

The fertility of the lands along the banks of Rideau river attracted loyalist settlers looking for good farmlands, which led to growth of settlements in the surrounding regions.

After the War of 1812, a waterway, designed by John By, was built through Rideau River connecting Kingston to Ottawa.