Bikes are allowed on the Red Loop, Green Loop, Yellow Loop and Blue Loop only. The Blue Loop is multi-use including horses. Stay off the horse trails. The park does close at 10:00 pm. The trails DO pass through hunting land; wear blaze orange in season. The trails are open year-round and there IS a groomed fat bike trail (part of the Green Loop) when there is more than 6" of snow on the ground.
Start at the mountain bike parking area. The Green Loop is now BIDIRECTIONAL. Ride COUNTERCLOCKWISE on Monday, Wednesday, Friday, and Sunday (ascending marker numbers). CLOCKWISE on Tuesday, Thursday and Saturday (descending marker numbers).
The Green Trail is a 99% hard packed singletrack surface, but there are plenty of rough and challenging sections. THIS TRAIL IS NOT FOR BEGINNER RIDERS, and plenty of people make that mistake. Once you are a mile into it, you have to ride the remaining six miles, unless you have a map that will allow you to take a shortcut after two miles of the toughest section. There are nice views of Eagle Lake along several stretches. There are two planked rollercoaster features which can be bypassed if beyond your skill level. Pay attention whenever the trail splits and follow the "easy" or "hard" marker. The only two-track is a quarter mile section that starts about a quarter mile into the ride and another quarter mile at the very end that is rapidly becoming straight and level singletrack.
Doing the Red and Green back-to-back gives you a great 15 mile ride that a fast rider can do in a little over an hour.