Sweet trail with some challenging sections of singletrack along a stream then followed by rugged Jeep road riding with very steep climbs and descents. One loop of many in the area.
Start on a singletrack and follow it upstream along St. Vrain Creek. Where the trail intersects the creek, take the uphill left on a steep, rocky Jeep road. At the top of the climb, turn left on a singletrack. The trail forks immediately. Turn left again and climb to the end of the trail at a dirt road. Turn right and descend to an intersection with several other roads. Take the third road from the left and descend on this very rocky, technically challenging road before climbing back to the point where you turned onto the single track above St. Vrain Creek. Descend to St. Vrain Creek, rejoin the St. Vrain Trail and return to the start.
From the end of the St. Vrain Trail there is a network of overgrown Jeep roads used primarily by mountain bikers and moto-crossers. This area abuts several tracts of private land and some of the roads end abruptly. You can't get too lost exploring the area, as there are only several miles of road, but all the intersecting trails can be confusing.
How to get there:
From Canyon and Broadway in Boulder, drive 3.4 miles north on Broadway to Lee Hill Rd.; turn left and drive six miles to Sunshine Canyon Rd. Turn right, drive one mile and turn left on left-hand Canyon Dr. Drive three miles to Jamestown and continue another 6.8 miles to the signed St. Vrain Trailhead. Turn right and park at the trailhead.