MTB Project Logo
Climb
MTB
Hike
Trailrun
Ski
Limited Time70% OffonX Backcountry

Coalton

Easy/Intermediate Easy/Intermediate
 2.5 (19)
  1. Areas
  2. CO
  3. …Front Range
  4. …Boulder
  5. Marshall Mesa
Explore MTB in 3D
Use onX Backcountry to explore the terrain in 3D, view recent satellite imagery, and more. Now available in onX Backcountry Mobile apps! For more information see this post.
Previous Next

“A mostly doubletrack/dirt road section connecting McCaslin Blvd with W 120th Ave. ”

Michael Ahnemann
Your Rating: Rating Rating Rating Rating Rating      Clear Rating
Your Difficulty:
Your Favorites: Add To-Do · Your List

2.8

Miles

4.5

KM
Doubletrack

5,949' 1,813 m

High

5,552' 1,692 m

Low

398' 121 m

Up

0' 0 m

Down

3%

Avg Grade (2°)

12%

Max Grade (7°)

Dogs Leashed

E-Bikes Allowed

E-bikes allowed per regulation: bouldercolorado.gov/guide/g…

Description

This section of trail is nothing special, but it makes up the southeast corner of the Dirty Bismarck ride. It allows riders to connect McCaslin and W 120th Ave. without riding any pavement.

Contacts

Local Club: Boulder Mountainbike Alliance

Nov 17, 2025: Trail Update: South St Vrain

Nov 14, 2025: Another Step Closer to new Betasso Connector

Oct 24, 2025: Boulder County Moves One Step Closer to a Safer Boulder-to-Betasso Connection

Land Manager: Boulder County, CO - Parks and Open Space

Shared By:

Michael Ahnemann with improvements by Austin Cowan
Full Details

Trail Ratings

  2.5 from 19 votes

#10

in Marshall Mesa

#25142

Overall
  2.5 from 19 votes
5 Star
11%
4 Star
16%
3 Star
11%
2 Star
42%
1 Star
21%
Trail Rankings

#10

in Marshall Mesa

#2,310

in Colorado

#25,142

Overall
4 Views Last Month
1,830 Since Mar 26, 2013
Easy/Intermediate Easy/Intermediate
44%
38%
13%
0%
6%
0%
Add a Photo

Photos

Front Range fun on Dirty Bismark
May 22, 2018 near Superior, CO
Coalton Hills.
Feb 26, 2018 near Superior, CO
Dirty Bismark heading west during a spring ride.
May 31, 2017 near Superior, CO
Sun setting this evening obscured by smoke from the wildfires in the north and west.
Aug 8, 2021 near Superior, CO
Looking east from the top of the hill, back to the Coalton Trailhead and car park.
Aug 8, 2021 near Superior, CO

2 Comments

Sort by: Oldest Drop down
Newest Oldest Popular
loading

Weather

Current Trail Conditions

Unknown
Add Your Check-In

Check-Ins

Oct 10, 2025
Anonymous
Aug 8, 2021
Private User
May 2, 2021
Sean Marlow
Aug 1, 2020
Holly S
First ride on my bike on flat tires. Very hard, walked some 2.8mi
Sep 10, 2019
Marc Barnes
Aug 2, 2019
Ted Graham
Straight downhill to ride taking it "backwards" on an easy day.
Sep 6, 2018
Katie Purdy
Jul 1, 2018
Jill Henske Keyes

Nearby Recommended Routes

Welcome

Join the Community! It's FREE

Already have an account? Login to close this notice.

Get Started