Entry to Michigan state parks is free on Black Friday

As part of the #OptOutside movement, Michigan state parks have no entrance fee on Black Friday. It's the perfect way to work off some of that Thanksgiving dinner!

All 79 of Michigan's state parks are free for visitors today, meaning residents can skip the usual $11 Recreation Passport.

Outdoor retailer REI launched #OptOutside in 2015. Instead of participating in Black Friday, REI stores were closed to encourage employees and customers to spend time outside.

Since its beginning, more than 700 organizations and 7 million people have participated, according to REI. Dozens of nonprofit and government agencies have partnered with REI for this event, including the Michigan Department of Natural Resources and the Land Conservancy of West Michigan.

Even Gov. Rick Snyder was tweeting about Michigan's state parks.

The U.S. Department of the Interior joined the movement and tweeted Thursday encouraging people to "#OptOutside for fun with friends and family."

You can even plan your outing online with help from the National Park Service.

More: 5 ways to #OptOutside and 2 major reasons you should

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