The Canadian Encyclopedia — neutral, cited, updated
July 27, 2026Sources cited
Canadianwire.
Canada’s encyclopedia & explainer
HomeCanadaProvinceOntario
Canada • Province

Ontario

Ontario is a province in east-central Canada and the country’s most populous province.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 27, 2026|2 min read| Fact-checked

Ontario is a province in east-central Canada and the country’s most populous province. It is bordered by Manitoba, Quebec, Hudson Bay, James Bay, the Great Lakes, and several U.S. states. The provincial capital is Toronto, while Ottawa, Canada’s national capital, is also located in Ontario.

Geography

Ontario’s maps typically show its provincial boundary, coastline, major lakes and rivers, and internal municipal or political divisions. Reference maps also include relief and selected roads, reflecting the province’s large size and varied landscapes.

Borders and location

Ontario lies in east-central Canada and shares borders with Manitoba and Quebec, as well as Hudson Bay, James Bay, the Great Lakes, and the United States. Its location makes it a central part of Canada’s transportation and population network.

Administrative divisions

Maps of Ontario often identify counties, regional municipalities, districts, and single-tier municipalities. These divisions are important for understanding local governance and regional geography.

Official mapping

The Government of Ontario publishes an official road map and other provincial maps. The official road map was first produced in 1923 and has been issued in new editions every two years since then.

Key facts

  • Ontario is one of Canada’s ten provinces and is located in east-central Canada.
  • It is Canada’s most populous province and second-largest province by area after Quebec.
  • Ontario borders Manitoba to the west and Quebec to the east.
  • Toronto is the provincial capital, and Ottawa, Canada’s national capital, is also in Ontario.
  • Ontario’s official road map has been produced since 1923 and is updated every two years.
🍁
Canadian context

Ontario is central to Canada’s population, economy, and transportation network, and it contains both Toronto and Ottawa, making it especially significant for Canadian readers.

Frequently asked questions

What is Ontario?
Ontario is a Canadian province in east-central Canada and the country’s most populous province.
What is the capital of Ontario?
Toronto is the capital of Ontario.
What is Ontario’s official abbreviation?
ON.
What does an Ontario map usually show?
It commonly shows the provincial boundary, coastline, major lakes and rivers, roads, and political or municipal divisions.
When was Ontario’s official road map first produced?
It was first produced in 1923.

References

  1. Government of Ontariohttp://www.ontario.ca/page/official-road-map-ontario
    Supports: Official road map history and publication cycle; Ontario road map features.
  2. Government of Canada Open Government Portalhttps://open.canada.ca/data/en/dataset/77cbc287-6b17-5ab6-bf2d-d61cee44356c
    Supports: Outline map of Ontario with boundary, coastline, and major lakes and rivers.
  3. Government of Ontariohttps://www.ontario.ca/page/maps-ontario
    Supports: General Ontario maps page.
  4. Natural Resources Canadahttps://natural-resources.canada.ca/maps-tools-publications/maps/atlas-canada/reference-maps
    Supports: Political, outline, and relief reference maps of Ontario.
  5. Geology.comhttps://geology.com/canada/ontario.shtml
    Supports: Ontario borders and geographic location.