Arkansas State Parks Trip Ideas Filter Park [X] Devil's Den Region Northwest Park Activity [X] Mountain Biking Trail Type Mountain Biking Trail Difficulty Author Meg Matthews Monika Rued Date Published January 2019 [X] November 2016 Video Blog: Mountain Biking…Squirrel! Nov 2016 ⁄ Meg Matthews The popularity of mountain biking has exploded in Arkansas. With mild fall temperatures and beautiful autumn color, now is the time to get on your bike and ride. A Sacred Place – The Fossil Flats Mountain Bike Trail Nov 2016 Fossil Flats is a six mile trail tucked away in Devil's Den State Park that is home to the Arkansas Mountain Bike Championships and Ozark Mountain Bike Festival. Arkansas State Park IMBA World Summit Bookend Rides Nov 2016 ⁄ Monika Rued Arkansas State Parks has been involved in mountain biking since the 1980s and still have a variety of rides, competitions, trails and bike shops.