Transportation

Historically, the province has used two major east-west routes, both starting from Montreal in the neighbouring province of Quebec. The northerly route, which was mostly pioneered by early fur traders, travels west from Montreal along the Ottawa River, then continues northwestward towards Manitoba. Major cities on or near the route include Ottawa, North Bay, Sudbury, Sault Ste. Marie, and Thunder Bay. The southerly route, which was driven by growth in settlements originated by the United Empire Loyalists and later other European immigrants, travels southwest from Montreal along the St. Lawrence River, Lake Ontario, and Lake Erie before entering the United States in Michigan. Major cities on or near the route include Kingston, Oshawa, Toronto, Mississauga, Kitchener-Waterloo, Hamilton, London, Sarnia, and Windsor. This route was also heavily used by immigrants to the Midwestern US particularly in the late 19th century.

Roads Main article: Roads in Ontario

400-Series Highways make up the primary vehicular network in the south of province, and they connect to numerous border crossings with the U.S., the busiest being the Detroit–Windsor Tunnel and Ambassador Bridge (via Highway 401) and the Blue Water Bridge (via Highway 402). Some of the primary highways along the southern route are Highway 401, Highway 417, and Highway 400, while other provincial highways and regional roads inter-connect the remainder of the province.

Waterways

The Saint Lawrence Seaway, which extends across most of the southern portion of the province and connects to the Atlantic Ocean, is the primary water transportation route for cargo, particularly iron ore and grain. In the past, the Great Lakes and St. Lawrence River were also a major passenger transportation route, but over the past half century passenger travel has been reduced to ferry services and sightseeing cruises.

Railways

Via Rail operates the inter-regional passenger train service on the Quebec City – Windsor Corridor, along with The Canadian, a transcontinental rail service from Southern Ontario to Vancouver, and the Sudbury – White River train. Additionally, Amtrak rail connects Ontario with key New York cities including Buffalo, Albany, and New York City. Ontario Northland provides rail service to destinations as far north as Moosonee near James Bay, connecting them with the south.

Freight rail is dominated by the founding cross-country Canadian National Railway and CP Rail companies, which during the 1990s sold many short rail lines from their vast network to private companies operating mostly in the south.

Regional commuter rail is limited to the provincially owned GO Transit, and serves a trainbus network spanning the Golden Horseshoe region.

The Toronto Transit Commission operates the province's only subway and streetcar system, one of the busiest in North America. OC Transpo operates, in addition to bus service, Ontario's only light rail transit line, the O-Train in Ottawa. Currently, a light-rail metro called the Confederation Line is under construction in Ottawa. It will have 13 stations on 12.5 kilometers and part of it will run under the city'sDowntown and feature three subway stations.

Air travel

Important airports in the province include Toronto Pearson International Airport, which is the busiest airport in Canada, Ottawa Macdonald-Cartier International Airport and Hamilton's John C. Munro Hamilton International Airport. Toronto/Pearson and Ottawa/Macdonald-Cartier form two of the three points in Canada's busiest set of air routes (the third point being Montréal-Pierre Elliott Trudeau International Airport).

Most Ontario cities have regional airports, many of which have scheduled commuter flights from Air Canada Jazz or smaller airlines and charter companies — flights from the mid-size cities such as Thunder Bay, Sault Ste. Marie, Sudbury, North Bay, Timmins, Windsor, London, and Kingston feed directly into larger airports in Toronto and Ottawa. Bearskin Airlines also runs flights along the northerly east-west route, connecting Ottawa, North Bay, Sudbury, Sault Ste. Marie, Kitchener and Thunder Bay directly.

Isolated towns and settlements in the northern areas of the province rely partly or entirely on air service for travel, goods, and even ambulance services (MEDIVAC), since much of the far northern area of the province cannot be reached by road or rail.

Highway 401 is the busiest highway in North America and among the busiest highways in the World.

A GO Transit commuter train.

Air Canada is the largest airline operating in Ontario.