Name: Coal Seam
Rating: 3.7

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Dogs Leashed

E-Bikes Allowed

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

Description

A fun connector with an extremely rocky option, and a very easy walking path option. The trail heads south, paralleling 93, and works its way up to a connection with Community Ditch.

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: City of Boulder, Colorado - Parks and Recreation

Shared By:

Garrett Lodewyck with improvements by Austin Cowan

Full Details

Trail Ratings

3.7 from 14 votes

#2

in Marshall Mesa

#12011

Overall

3.7 from 14 votes

5 Star		7%
4 Star		57%
3 Star		36%
2 Star		0%
1 Star		0%

Trail Rankings

#2

in Marshall Mesa

#1,157

in Colorado

#12,011

Overall

2 Views Last Month

916 Since May 1, 2013

		7%
		14%
		71%
		7%
		0%
		0%

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Photos

Heading out from the trailhead, the smooth wide trail awaits - much like most of the DIrty Bismarck surface.

Mar 26, 2013 near Superior, CO

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Coal Seam

“Super fun connector trail at Marshall Mesa trailhead. ”

0.6

0.9

5,718' 1,743 m

5,567' 1,697 m

151' 46 m

0' 0 m

5%

9%

Toolbox

Know This Trail?

Dogs Leashed

E-Bikes Allowed

Description

Contacts

Shared By:

Trail Ratings

#2

#12011

#2

#1,157

#12,011

Photos

1 Comment

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