Ottawa is the capital city of Canada. It is located in the southern portion of the province of Ontario, at the confluence of the Ottawa River and the Rideau River. Ottawa borders Gatineau, Quebec, and forms the core of the Ottawa–Gatineau census metropolitan area (CMA) and the National Capital Region (NCR). As of 2021, Ottawa had a city population of 1,017,449 and a metropolitan population of 1,488,307, making it the fourth-largest city and fourth-largest metropolitan area in Canada.

A capital city or just capital is the municipality holding primary status in a country, state, province, department, or other subnational division, usually as its seat of the government. A capital is typically a city that physically encompasses the government's offices and meeting places; the status as capital is often designated by its law or constitution. In some jurisdictions, including several countries, different branches of government are in different settlements, sometimes meaning multiple official capitals. In some cases, a distinction is made between the official (constitutional) capital and the seat of government, which is in another place.