Centennial Cone is a sweet mountain bike loop in the foothills north of Clear Creek Canyon. Drive up Clear Creek Canyon and turn off the highway at Douglas Mountain Road, then, follow signs to Centennial Cone Trailhead. The trail is mostly single track, always ride-able, no big ups, not rocky, and no technical sections. Just baby-butt fun. Alex H. recommends riding the 12 mile loop clockwise. There is also a northern trailhead approached from the Golden Gate Canyon Road. You can also ride up from Clear Creek on the new Mayhem Gulch Trailhead parking area which provides a direct linkup to the Cone loop.