Ontario lies on a low plateau, crossed by two ranges of low hills. It has four main land regions. They are, from north to south:

(1) The Hudson Bay Lowland
(2) The Canadian Shield
(3) The St. Lawrence Lowland
(4) The Great Lakes Lowland

The Hudson Bay Lowland curves around the southern part of Hudson Bay and extends as far south as Kesagami Lake. This flat region of northern Ontario is poorly drained, and has large muskegs (peat bogs). The lowland includes a narrow belt of permafrost (permanently frozen ground) near the Arctic.

The Canadian Shield is a vast, horseshoe-shaped region that covers almost half of Canada and part of the northern United States. This low, rocky region covers about half of Ontario. Small lakes and rivers surrounded by wooded hills attract many vacationers. The highest point in Ontario rises 2,275 feet (693 meters) in Timiskaming District.

The Canadian Shield is rich in game, minerals, and timber. Patches of clay are scattered throughout the region. These areas were formed by the soil of ancient glacial lakes. The largest clay area, known as the clay belt, extends from the Hearst area to the Quebec border. Farmers raise a variety of crops, including grains and vegetables, in the rich clay soil. Beef and dairy cattle graze on fenced grasslands.

The St. Lawrence Lowland runs along the St. Lawrence River. In Ontario, it forms the tip of the wedge of land between the Ottawa and St. Lawrence rivers. Low hills rise above the fertile valleys. Farmers grow fruits, grains, and vegetables. Dairy farming is extensive there.

The Great Lakes Lowland lies along much of the Great Lakes in Canada and the United States. In Ontario, the region touches Lakes Erie, Huron, and Ontario. Great quantities of many crops are grown in the fertile gray brown soil of the low, fiat, southwestern section. The land rises gently in the northeast, where beef and dairy cattle are raised. The Niagara Escarpment, a high cliff or ridge, extends 250 miles (402 kilometers) from Manitoulin Island, through Bruce Peninsula, to Niagara Falls. The escarpment forms a natural shelter for Ontario's best fruit growing belt. Many of Canada's largest cities are in Great Lakes Lowland.