The Rideau Canal, also known as the Rideau Waterway, connects the city of Ottawa, Ontario on the Ottawa River to the city of Kingston, Ontario on Lake Ontario. The Rideau Canal includes sections of the Rideau River and the Cataraqui River, as well as several lakes including the Lower, Upper and Big Rideau lakes. The Rideau Canal was completed in 1832 and continues to be operated today. Many of the locks are still hand-operated. Its construction was supervised by Lieutenant Colonel John By.

At the time it was built there was a real threat of attack by the United States. Inspired by the War of 1812, the threat was real. The possibility future American attacks had to be mitigated and/or deterred.

Its initial purpose was military - to provide a secure supply route between Montreal and Kingston, Ontario. So westward from Montreal, travel would proceed along the Ottawa River to Ottawa, then southwest via the canal to Kingston (and vice versa for eastward travel from Kingston to Montreal). The key being to bypass the stretch of the St. Lawrence River bordering then Upper Canada (now the Province of Ontario) and New York State which would have left British ships vulnerable.

No further military encounters ocurred between Canada and the United States since the canal was constructed, and consequently the Rideau Canal was never used for its intended purpose.

Today, the Rideau Canal transports only pleasure craft for recreational use and also serves as a tourist attraction. In winter, a section of the Rideau Canal which passes through the city of Ottawa becomes the world's longest skating rink.

Locks entering the Ottawa River