Mackinac Island's surroundings are composed of Lake Huron, a large lake located in the province of Ontario, Canada. It is the second largest of the five Great Lakes and is bordered by the Canadian province of Ontario to the north and the U.S. states of Michigan, Wisconsin, Ohio, and Pennsylvania to the south. The lake is connected to the other Great Lakes by the St. Lawrence River and is home to many species of fish, birds, and other wildlife. Mackinac Island is located in the Straits of Mackinac, which connects Lake Huron to Lake Michigan.