Near Dirty Bismark
Great views
Near Dirty Bismark
Looking east to the sunrise along the Greenbelt Plateau Trail. July 2015.
Near Dirty Bismark
Looking west from the Greenbelt Plateau toward the flatirons.
Near Dirty Bismark
Looking northwest from the little spur road to the reservoir. Nice view!
Near Dirty Bismark
Colorado morning sunrise from the High Plains Trail

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Driving Directions
Hike Route

Dirty Bismark

4.0 (23 Ratings)
A rare, long, flat-ish loop on dirt in the Front Range, named after the Morgul Bismarck road cycling route.
15.2
mi
Distance
949
ft
Gain
moderate
Difficulty
Access Issues
Parking fees apply at select parking lots.Please be courteous in regards to trail closures. Large portions of this trail are clay and are therefore easily damaged while wet. Check this website for any current closures: https://maps.bouldercolorado.gov/osmp-trails/?

Route Details

Flatter
Steeper
15.15mi
Distance
949ft
Elevation Gain
949ft
Elevation Loss
30%
Max Grade
5,963ft
High Point
5,517ft
Low Point
Path Type
Loop
Description
You can start at the !Marshall Mesa Trailhead as shown here, but there are numerous trailheads along the loop for access. The route description is clockwise from Marshall Mesa.Start by heading east on Marshall Valley. You'll come to the intersection with Community Ditch, but stay straight to head east on Cowdrey Draw. You'll cross a small side road where the trail turns into Mayhoffer Singletree. Keep following the obvious route. This turns into Meadowlark. At the bottom of the hill is a small parking lot with restrooms. From here, turn right to climb up the doubletrack Coalton. Watch for cows and prairie dogs. Coalton will take a sharp left at the top of the hill and wind back toward 128 where you'll find another small parking area. From here, the trail becomes the High Plains trail with finally some nice flowing singletrack. At the end of this singletrack section is the Greenbelt Plateau parking area. At the parking area, turn right to follow the doubletrack up the hill. At the very end of Greenbelt Plateau you'll encounter a small rock feature and intersect with Community Ditch. Turn left onto Community Ditch until you reach the intersection for Coal Seam. Take a hard right to follow the slightly rock Coal Seam back down to the !Marshall Mesa Trailhead.
History & Background
The Morgul Bismarck is a relatively famous stage from the Red Zinger / Coors Classic road cycling race from the 1970's and 1980's. Over time, trails along the perimeter of this classic road route have been built, making the Dirty Bismarck MTB trail.

Route Conditions

Report Conditions
No Condition Reports
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Contributors
Amanda Stone