The Port Huron Float Down was Sunday.
People in tubes and rafts hopped into the water at Lighthouse Beach in Port Huron, about 55 miles northeast of Detroit, and floated down the St. Clair River to Chrysler Beach in Marysville.
Thousands of people turned out for the event.
Waterways were closed to motor vessels from 11 a.m. to 8 p.m., to keep the river clear for Float Down participants.
The U.S. Coast Guard, the St. Clair County Sheriff Department and other agencies were on hand to monitor the annual event.