Fourmile Link Trail

Trail Meter: 

Get ready for a lung-buster!

This 0.8 mile trail allows you to access the Betasso Preserve trail system from Fourmile Canyon.  To use this trail, you should ride from town - there is no parking and no trailhead at Fourmile Canyon Road.

This trail also enables more adventurous (stubborn? jonesing for miles?) mountain bikers to make a loop from Boulder without repeating trail - check out the Super Betasso route description for more info.

The Fourmile Link Trail is possible due to one of the most exciting recent open space purchases by Boulder County Parks and Open Space (BCPOS). After acquiring 400 acres to the north and west of Betasso Preserve, BCPOS decided to build an additional 4 or so miles of trail that connect to the Canyon Loop Trail, and the Benjamin Loop (2011) and Fourmile Link were born.  Whenever you see some County staff on the trails, thank them for building this awesome shared use trail!

Important stuff you should know:

  • This trail is closed to bikes on Wednesdays and Saturdays
  • Expect two-direction traffic, so look ahead and watch for other trail users.
  • There is no formal trailhead on Fourmile Canyon Drive, and no parking along that stretch of road, so BMA recommends riding your bike from town if you want to access Betasso Preserve from this trail.

Please obey these rules and BMA will continue to work within the political process to make the system work better!


Fourmile Link Trail KMZ7.85 KB
Fourmile Link Trail GPX70.14 KB
Fourmile Link Trail Click on image to enlarge

T: 6 A: 6 C: 7

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0.8 mi.
350 ft.


Trail Meter: Good»Closed

BCPOS closure: Runoff has started. COLD FAST DEEP WATER. Do not attempt.

With the warm temps the runoff has made the creek impassable.

Dirt is great. Had to carry my bike across the creak. Freezing runoff is creeping up in the evening.

condition set to Good

condition set to Fair

Lots of rain and snow today. Will need several good days of sun.

Trail Meter: Poor»Good

Mud dried up.....great conditions

Snow! (so great if you have a fat bike!) And soon to be very muddy.

Trail Meter: Poor»Good

Bridge is still out at stream, however, open space has dropped some rocks, so you can get across. A few small patches of ice, mostly dry.


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