This section runs between 9200-10200' elevation. The altitude, climbs, and constant rockiness make this an overall tough ride. There aren't many large-rock sections, but plenty of small-medium ones to keep it a little rough most of the time, and many small sharp ones that have given me pinch flats and holes in the sidewalls. As of 2012 it seems they've done some trail work and smoothed out several sections that where once much harder. There are several fallen trees you'll have to work around, some have been turned into fun little log piles to ride over. The ride is mostly through dense forrest perfect for hot summer days. There are maps at both ends of the trail, check out the map at the north end to see more trail options that continue from the trailhead on Brainard Lake Rd.
From Boulder, head up to Nederland. Go right(north) on Highway 72 for aboug 7 miles. Turn left onto County Road 116 (there's a sign for the University of Colorado Mountain Research Station). go about .5 mile to the parking lot on the left, trail starts across the road, this is the south end of the trail.<br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br />http://maps.google.com/maps?q=nederland,+co&hl=en&ll=40.027549,-105.524712&spn=0.036871,0.06669&hnear=Nederland,+Boulder,+Colorado&t=m&z=14<br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br />There's another trailhead further north, from Ward, head up Brainard Lake Rd, there's a large nice new parking area on the right just before you get to the Toll gate. For this stretch of Sourdough, most of the climbing is done heading North from the South end, and mostly downhill going South.
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