Winter Antics at Milliken State Park. Saturday, February 15th from 11-2pm. Time for some winter hijinks! We're offering up snowshoeing, bonfires & s'mores, snow games like tug-o-war, tips on winter wear and staying warm, all while watching those brave souls take the polar plunge in the Detroit River. No need to bring anything ... just your warmly-dressed selves. This event is FREE. Free parking is available at Rivard Plaza, 1340 Atwater Street. Come participate in this amazing event at Michigan's first urban state park – William G. Milliken State Park and Harbor. **An $11 Recreation Passport is required for entering State Parks, Recreation Areas, State Forest Campgrounds, Non-motorized Trail Head Parking and Boat Launches. Recreation Passports can be purchased when renewing your State of Michigan license plate tabs or at state parks and recreation areas.