The Ceran Saint Vrain Trail is an easy trail that gradually loses elevation as it follows the South Saint Vrain Creek downstream for 1.9 miles. The trail ends at National Forest System Road 252, a rough four-wheel drive road. This road climbs 0.5 miles northwest to a four-way intersection from which it is a steep half-mile to the left up to Miller Rock. Miller Rock is a scenic high-point that offers 360-degree views.
From Intersection of Broadway and Canyon in Boulder, go 3.4 miles north on Broadway to Lee Hill Road. Take Lee Hill Road to Old Stage Road and go 4 miles to Lefthand Canyon Road, go left 2 miles to County Road 94 to Jamestown, go 4.7 miles to the enterance for Ceran Saint Vrain, turn right into the trailhead parking lot. (Information provided by "Mountain Biking Denver and Boulder") <br />a Simpler way would be to go north(or west as the book says) on Highway 36, there will be a sign for Jamestown where you will take a left, continue untill you reach the Ceran Saint Vrain parking lot enterance on the right, don't drive to fast or you'll fly right past it as I have a few times:o)
http://www.tripleblaze.com/trail.php?c=3&i=902