Southwestern Ontario is a region of the Canadian province of Ontario, centred on the city of London. It extends north to south from the Bruce Peninsula on Lake Huron to the Lake Erie shoreline, and east to south-west roughly from Kitchener to Windsor. These three urban centres make up the majority of the population of 2,328,987 in 2001. Other significant towns and cities in the region are Chatham, Ingersoll, Owen Sound, Sarnia, St. Thomas, Goderich, Stratford, Tillsonburg and Woodstock. The Bruce Peninsula and Georgian Bay shoreline, including the Blue Mountains are also part of the Georgian Triangle. Another popularly-mentioned sub-region within Southwestern Ontario is "Midwestern Ontario", stretching from roughly Lake Huron to Lake Erie, containing Bruce, Grey, Dufferin, Wellington, Perth, Huron, and Oxford Counties, with some definitions extending into Brant County, and even Halton Region and Norfolk County. The major centres in this region are Wingham, Goderich, Mount Forest, Walkerton, Hanover, Collingwood, Owen Sound, Woodstock, London, Ingersoll, Tillsonburg, and Delhi, with Brantford and Orangeville occasionally being considered part of the area. In short, Midwestern Ontario is considered as the eastern quarter of the region along the edge of the Greater Toronto Area, and stretching back through the hilly regions near Shelburne, back towards Goderich and Kincardine. Some definitions reach eastward to include Guelph and Orangeville, though recently these municipalities are also included in on the western side of the growing Greater Golden Horseshoe region and many of their residents commute into the Greater Toronto Area. Southwestern Ontario constitutes the western portion of the original province, present-day southern Ontario, which was first settled as Upper Canada prior to 1840. The region may also be referred to as Western Ontario, particularly in the names of institutions such as the University of Western Ontario. This term is falling into disuse, however. Western Ontario may also designate all the counties of southwestern Ontario except Essex, Kent, and Lambton—that is, the region of which London, Ontario is the central city. Western Ontario was so called because until Ontario expanded in 1912 to incorporate Northern Ontario it was the westernmost part of the most populated section of the province. Southwestern Ontario is a prosperous agricultural region whose chief crops are tobacco, sweetcorn, soybean, winter wheat, canola, and tomatoes. Dairy and beef farming, breeding and training of standardbred horses and wine growing and production are also important industries. Its climate is among the mildest in Canada, although brief periods of winter can be severe, summers are hot and humid with a longer growing season than most of the country. A large section of Southwestern Ontario was part of the Talbot Settlement, and the region has benefited from the settlement’s facilitation of agriculture and of trade in general. Its ecomony is heavily tied in with that of the midwestern United States, in particular the border state of Michigan. Auto manufacturing and parts, agriculture and hi-tech industries are key components of the region’s economy. The region also provides important transportation routes for commercial trucking, railway and tanker shipping from Detroit-Windsor and Port Huron, Michigan-Sarnia linking Canada with major markets in the eastern and midwestern United States.
List of counties or divisions
- Essex County
- Chatham-Kent
- Lambton County
- Elgin County
- Middlesex County
- Huron County
- Perth County
- Bruce County
- Grey County
- Waterloo Region
- Wellington County
- Oxford County
- Brant County
- Norfolk County
- Haldimand County
Southwestern Ontario 
Subdivisions of 
