Coast to Coast to Coast
Canadian geography in 24 lessons, with Nora Beaulieu
Module 7 · Regions up close · Lecture 19

Ontario: the lowlands, the Shield and the far north

Half of Canada's people on its smallest landform region; the Niagara Escarpment and the Greenbelt; Sudbury's nickel and Timmins' gold; nuclear power and auto plants; and the Hudson Bay coast most Ontarians never see. Skill: NTS sheet numbers and a six-figure grid reference.

All lectures Take the quiz

Test yourself

1. Which landform region holds about half of Canada's people?
The Lowlands are the smallest of the seven regions and hold about half the population, including Toronto, Ottawa and Montreal.
2. What is the highest point in Ontario?
Ishpatina Ridge, on the Shield, is Ontario's highest ground in the Atlas of Canada tables, less than seven hundred metres.
3. According to the Canada Energy Regulator, what was the biggest source of Ontario's electricity in twenty twenty-one?
Nuclear plants supplied fifty-five per cent of Ontario's electricity in twenty twenty-one, with hydro second.
4. On the lettered one to fifty thousand sheet, grid line forty-two is left of the point and the point is six tenths across; line seventy-one is below it and the point is two tenths up. What is the six-figure grid reference?
Easting first, forty-two and six tenths, then northing, seventy-one and two tenths, gives four two six, seven one two.
5. Which of these is inside Ontario's Greenbelt Plan area, created in two thousand and five?
The Greenbelt Plan area includes the Niagara Escarpment Plan area, the Oak Ridges Moraine and the Protected Countryside around the Greater Golden Horseshoe.
Transcript

Rattlesnake Point, above Milton, Ontario, on a cold October afternoon. Grace Adeyemi is fifteen, Nigerian-Canadian, in Grade 9, and her class has climbed the Niagara Escarpment on a field trip. Below her the farms run east to the towers of the Greater Toronto Area. Her assignment is the one this lecture models: a six-figure grid reference for the spot where she is standing.

So here's the question. How does one province hold Canada's biggest city, the national capital, a nickel camp, a giant nuclear station, and a Hudson Bay coast most Ontarians never see?

Statistics Canada put Ontario at 16.1 million in April 2026, and in the 2021 census it held 38.5% of Canadians. Most are on the smallest of the seven landform regions, the Great Lakes–St. Lawrence Lowlands, with Toronto's metropolitan area at 7.1 million in 2025. Ottawa, not Toronto, is the seat of government, under section 16 of the Constitution Act, 1867.

North of the lowlands is the Shield, most of the province by area. Its highest point, Ishpatina Ridge, is 693 m by the Atlas of Canada. In 2024, Natural Resources Canada says, Ontario mined 40% of Canada's nickel and 40% of its gold, mostly around Sudbury and Timmins. Beyond the Shield lie the Hudson Bay Lowlands, flat and wet, ending at Moosonee and Polar Bear Provincial Park.

Ontario also makes things. The Canada Energy Regulator reports that in 2021 nuclear plants supplied 55% of the province's electricity, and that Bruce, at 6,232 MW, is one of the largest nuclear stations in the world. Invest Ontario counts more than 1.2 million vehicles built in 2025 by five assemblers.

Find it on the map. This is a Toporama sheet at 1:50,000 from Natural Resources Canada, and north is at the top. The blue grid lines are one kilometre apart, numbered along the edges. Easting first: the line to the left of the point, then tenths across. Then the northing, the line below, then tenths up. Six figures, and Grace's spot on the cliff is fixed to within 100 m.

Every NTS sheet also carries a number, like 031G05 for Ottawa. As a demonstration: 031 is the big block, G the 1:250,000 quarter, 05 the 1:50,000 sheet inside it. With your own sheet number you can order the paper map.

Let's change one fact. Move the Frontenac Axis, the finger of Shield that crosses the St. Lawrence at Kingston, 200 km west. Now the granite reaches the lakeshore at Toronto. The city sits on thin soil and bare rock instead of deep clay and old lake bed. No market gardens, no orchards, and a much smaller city.

The mistake people make is saying Ontario is all cities. By area, the Shield and the Hudson Bay Lowlands are most of the province. And the Greenbelt, created in 2005, sets aside the Escarpment, the Oak Ridges Moraine and the Protected Countryside right beside the biggest city. The other mistake: Toronto is Ontario's capital. Canada's is Ottawa.

Here's the rule, in one breath. A small lowland with most of the people, a big Shield with most of the metal, a wet northern coast with hardly anyone, and Canada's capital is Ottawa.

This week, open Toporama, zoom to 1:50,000 over your own street, and write a six-figure grid reference for your front door. Then check it against the scale bar: one centimetre on that sheet is half a kilometre.

Next time, the Prairies: three steps rising to the west, a survey grid you can see from orbit, and a dry triangle.

← Lecture 18: Quebec: the Shield, the river and the hydroLecture 20: The Prairies: three steps, a grid and a dry triangle →
Free, independent course. Not an official resource of Immigration, Refugees and Citizenship Canada or of any Ministry of Education. Facts are from Statistics Canada, Natural Resources Canada, Environment and Climate Change Canada and other government sources, as dated in each lecture; figures change, so check the source for the latest. Maps are drawn from Natural Earth (public domain); photographs are from Wikimedia Commons under open licences, credited on the maps and photos page. Nora Beaulieu is an AI-generated presenter with a synthetic voice. Course content © 2026.