Which lake has the longest shoreline of any freshwater lake?

Lake Huron has the longest shoreline of any named freshwater lake, counting its many islands and bays.

Its shoreline measures roughly 3,827 miles, or 6,157 kilometres, including more than 30,000 islands. Georgian Bay and Saginaw Bay add extensive irregular coast, while Manitoulin Island contributes to the lake's remarkable shoreline complexity.

Lake Huron is shared by Canada and the United States and is the second-largest Great Lake by surface area. Its average depth is about 59 metres, while its deepest point reaches approximately 229 metres. Manitoulin Island, in the lake, is the world's largest island located in a freshwater lake.

A frequent mix-up involves Lake Superior, which is larger by surface area and volume and therefore often feels like the obvious answer. There is also a technical qualification: Lake Michigan and Lake Huron are hydrologically one connected lake, so the combined Michigan–Huron system has an even longer coastline. In ordinary geographic naming, however, Lake Huron is the accepted answer.