Ontario (IPAEng: ɒnˈtɛri.oʊ) is a province located in the central part of Canada, the largest by population and second largest, after Quebec, in total area. (Nunavut and the Northwest Territories are larger but are not provinces.) Ontario is bordered by the provinces of Manitoba to the west, Quebec to the east, and the U.S. states (from west to east) of Minnesota, Michigan, Ohio, Pennsylvania (at Lake Erie), and New York. Most of Ontario's borders with the United States are natural, starting at the Lake of the Woods and continuing through four of the Great Lakes: Superior, Huron (which includes Georgian Bay), Erie, and Ontario, then along the Saint Lawrence River near Cornwall. Ontario is the only Canadian Province that borders the Great Lakes.

The capital of Ontario is Toronto, the largest city in Canada. Ottawa, the capital of Canada, is located in Ontario as well. The 2006 Census counted 12,160,282 residents in Ontario, which accounted for 38.5% of the national population.

The province takes its name from Lake Ontario, which is thought to be derived from ontarí:io, a Huron word meaning "great lake", or possibly skanadario which means "beautiful water" in Iroquoian. Along with New Brunswick, Nova Scotia and Quebec, Ontario is one of the four original provinces of Canada when the nation was formed on July 1, 1867, by the British North America Act.

Ontario is Canada's leading manufacturing province accounting for 52% of the total national manufacturing shipments in 2004.

Geography

Main: Geography of Ontario

• The thinly populated Canadian Shield in the northwestern and central portions which covers over half the land area in the province; though mostly infertile land, it is rich in minerals and studded with lakes and rivers; sub-regions are Northwestern Ontario and Northeastern Ontario.
• The virtually unpopulated Hudson Bay Lowlands in the extreme north and northeast, mainly swampy and sparsely forested; and
• The temperate and therefore most populous region, the fertile Great Lakes-Saint Lawrence Valley in the south where agriculture and industry are concentrated. Southern Ontario is further sub-divided into four regions; Southwestern Ontario (parts of which were formerly referred to as Western Ontario), Golden Horseshoe, Central Ontario (although not actually the province's geographic centre) and Eastern Ontario.