Lake Huron dominates the Great Lakes with approximately 30,000 islands, while Lake Erie has just 31, highlighting the striking geographical differences across North America’s freshwater giants.
The five Great Lakes of North America are famous for their enormous freshwater reserves but they also contain thousands of islands spread unevenly across their waters. Lake Huron has by far the highest number, with around 30,000 identified islands, while Lake Erie has the fewest, with just 31.
The exact figures can vary depending on how islands are defined and counted, particularly when it comes to tiny rocky outcrops and archipelagos near river boundaries.
1. Lake Huron – Around 30,000 islands
Lake Huron tops the list with approximately 30,000 islands, many of them concentrated in Georgian Bay along the Ontario shoreline.
Some estimates suggest Georgian Bay alone contains more than 30,000 islands, although many are tiny rocky formations without substantial soil. The lake is also home to Manitoulin Island, the world’s largest freshwater island, covering approximately 1,068 square miles.
The region’s island rich landscape is largely linked to the ancient, erosion-resistant rocks of the Canadian Shield, which date back more than a billion years.
2. Lake Superior – Nearly 500 islands
Lake Superior, the largest of the Great Lakes by surface area, contains close to 500 islands.
Its most prominent island is Isle Royale, covering approximately 207 square miles. It forms part of Isle Royale National Park in Michigan and supports wildlife including moose and wolves.
Lake Superior is also home to the Apostle Islands, a group of 21 islands known for their striking sandstone cliffs, sea caves and ice caves.
3. Lake Michigan – Around 100 islands
Lake Michigan has approximately 100 islands, most of which are concentrated in its northern section.
The distribution is linked to the region’s geological history. Glacial movement during the retreat of the Laurentide Ice Sheet shaped the lake basin, while more erosion-resistant rocks in the north helped preserve island formations.
Beaver Island is the largest island in Lake Michigan, covering around 55.8 square miles. It is also known for its unusual history: religious leader James Jesse Strang established a community there and declared himself king in the mid-19th century.
4. Lake Ontario – Around 100 islands
Lake Ontario contains approximately 100 islands, although it is sometimes incorrectly associated with more than 1,000 because of the nearby Thousand Islands archipelago.
The famous Thousand Islands region actually lies along the St. Lawrence River, near the boundary between Ontario and New York, and contains 1,864 islands. Most are not officially counted as part of Lake Ontario.
Wolfe Island, covering around 48 square miles, is the largest island in the Lake Ontario region. It is a popular destination for cycling and outdoor recreation. Amherst Island is another notable island, located west of Kingston in Ontario.
5. Lake Erie – 31 islands
Lake Erie has the fewest islands among the five Great Lakes, with 31 identified by the Ohio Department of Natural Resources.
Most are located within Ohio’s boundaries and form part of a limestone archipelago. Kelleys Island, covering approximately 2,800 acres, is the largest island on the American side and is home to Kelleys Island State Park.
However, Pelee Island in Ontario is the largest island in Lake Erie, covering around 10,000 acres. Both islands are known for their vineyards and wine production, supported by the region’s relatively warm climate and fertile soil.
Despite their enormous numbers, most islands across the Great Lakes are small, remote and uninhabited. Only around 20 to 30 islands across the entire Great Lakes ecosystem have permanent human populations.
Some such as Mackinac Island, are known for tourism and settlements, while others serve as protected habitats for wildlife.
The islands also reflect the region’s complex geological history, shaped by ancient rock formations, glacial movements and erosion. Together, they make the Great Lakes not only one of the world’s largest freshwater systems but also an extraordinary landscape of islands, wilderness and biodiversity.