Awesome singletrack loops in Central Oklahoma. Four loops total, @ 6-7 miles each, 27 miles total. Well-marked trails, good trail map available at Ranger Office at Park entrances on both sides. Lots of shade, very few other bikers, take lots of bug spray and water. Short climbs, switchbacks in a forested and/or prairie environment! You can ride most of the trails fast, but there are some rock outcrops, rooted climbs, sometimes sandy corners, and a few washouts. Aerobic difficulty will depend on how many miles you ride; About 5 for one loop only. Trails are usually well maintained, but can be overgrown in the summer. Cooper's Bike shop on Main Street in Stillwater will have most of what you might need.