Algonac is a city in St. Clair County of the state of Michigan. Its population at the 2000 census was 4,613.
The Algonac City Park has a boardwalk along St. Clair River. The State Park is to the north of the city. The city sits on what is considered the largest freshwater delta in the world. Canals run through the city, earning it the nickname of "The Venice of Michigan".
The population predominantly comprises White Americans.