Ottawa is the capital of Canada, the second largest city in the Province of Ontario, and the fourth largest city in the country. Located in the Ottawa Valley, the city lies in the eastern portion of Southern Ontario on the Ottawa River, a major waterway forming the local boundary between the provinces of Ontario and Quebec.

Ottawa is connected by several bridges to its Quebec neighbour on the shores of the Ottawa River — the city of Gatineau. The two cities and surrounding area are designated the National Capital Region (NCR). Though governed by separate municipal governments, the federal lands within the region are administered by the National Capital Commission (NCC), a federal crown corporation charged with the responsibility of planning and managing the federal government's interests in the NCR.

In 2006, the city of Ottawa had a population of 812,129, making it the fourth-largest municipality in the country and second-largest in Ontario. The Ottawa-Gatineau metropolitan area had a 2006 population of 1,130,761, making it the fourth-largest census metropolitan area (CMA) in Canada. The National Capital Region which encompasses Ottawa, Gatineau and surrounding suburbs and towns has an estimated population of 1,451,415. In 2009 Ottawa-Gatineau's population was estimated at 1,220,674, making it the fifth-largest CMA in Canada. In 2010, Ottawa had the 2nd highest quality of living of any city in the Americas, and 14th highest in the world according to the "Mercer Human Resource Consulting Quality of Living Survey". It was also considered the 3rd cleanest city in the world by Mercers 2010 eco-city ranking.

Ottawa is situated on the south bank of the Ottawa River, and contains the mouths of the Rideau River and Rideau Canal. The oldest part of the city (including what remains of Bytown) is known as Lower Town, and occupies an area between the canal and the rivers. Across the canal to the west lies Centretown (often just called "downtown"), which is the city's financial and commercial hub. Situated between Centretown and the Ottawa River, the slight elevation of Parliament Hill is home to many of the capital's landmark government buildings, including the Peace Tower, and the legislative seat of Canada. As of June 29, 2007, the Rideau Canal, which stretches 202 km (126 mi) to Kingston, Fort Henry and four Martello towers in the Kingston area was recognized as a UNESCO World Heritage Site.

The City of Ottawa has a main urban area but there are many other urban, suburban and rural areas within the city's limits. The main suburban area extends a considerable distance to the east, west and south of the centre, and includes the former cities of Gloucester, Nepean and Vanier, the former villages of Rockcliffe Park and the community of Blackburn Hamlet (pop. 8,527), the community of Orléans (pop. 110,000). The Kanata suburban area consists of Kanata (pop. 90,000) and the former village of Stittsville (pop. 20,000). Nepean is another major suburb which also includes Barrhaven (pop. 70,000) and the former village of Manotick (pop. 7,545). There are also the communities of Riverside South (pop. 8,000) on the other side of the Rideau River, Morgan's Grant (pop. 8,000) and Greely (pop. 4,152), southeast of Riverside South. There are also a number of rural communities (villages and hamlets) that lie beyond the greenbelt but are administratively part of the Ottawa municipality. Some of these communities are Burritts Rapids (hamlet, pop. 300); Ashton (hamlet, pop. 300); Fallowfield (hamlet, pop. 600); Kars (village, pop. 1,539); Fitzroy Harbour (village, pop. 1,549); Munster (village, pop. 1,390); Carp (village, pop. 1,400); North Gower (village, pop. 1,700); Metcalfe (village, pop. 1,810); Constance Bay (village, pop. 2,327) and Osgoode (village, pop. 2,571) and Richmond (village, pop. 3,301). There are also a number of towns in the national capital region but outside the city of Ottawa, one of these urban communities is Almonte, Ontario (town, pop. 4,649).

Across the Ottawa River, which forms the border between Ontario and Quebec, lies the city of Gatineau, itself the result of amalgamation of the former Quebec cities of Hull and Aylmer together with Gatineau. Although formally and administratively separate cities in two separate provinces, Ottawa and Gatineau (along with a number of nearby municipalities) collectively constitute the National Capital Region, with a combined population exceeding one million residents, which is considered a single metropolitan area. One federal crown corporation (the National Capital Commission, or NCC) has significant land holdings in both cities, including sites of historical and touristic importance. The NCC, through its responsibility for planning and development of these lands, is an important contributor to both cities.

Around the main urban area is an extensive greenbelt, administered by the National Capital Commission for conservation and leisure, and comprising mostly forest, farmland and marshland.

Source: Wikipedia