The Great Lakes from space; Lake Huron is the third from the left.

Lake Huron is one of the five Great Lakes of eastern North America, and separates Michigan from Ontario. Georgian Bay, the easternmost part of Lake Huron, is entirely within Canada.

Lake Huron is separated from Lake Michigan, which lies at the same level, and connects by the narrow Straits of Mackinac, making them geologically the same body of water. Lake Superior is slightly higher than both. It drains into the St. Marys River at Sault Ste. Marie which then flows southward into Lake Huron. The water then flows south to the St. Clair River, at Port Huron, Michigan and Sarnia, Ontario.

The Great Lakes Waterway continues thence to Lake St. Clair, the Detroit River and Detroit, Michigan, into Lake Erie and thence, via Lake Ontario and the St. Lawrence River, to the Atlantic Ocean.

The surface of Lake Huron is 579 feet (176 metres) above sea level, and the lake's maximum depth is 750 feet (230 metres). It covers an area of about 23 000 square miles (59 600 square kilometres). It contains 3,538 cubic km of water. Like the other Great Lakes, it is the remnant of the larger Glacial Lake Agassiz, formed by melting ice as the continental glaciers retreated.

A notable feature of the lake is Manitoulin Island, the world's largest lake island.