22.5 miles
Distance
1,627 ft
Climb
-1,628 ft
Descent
1 mile
High Point

Links Dirty Bismark with Springbrook and trails west of 93. Many different lots to start from other than the Marshall Mesa parking lot... Or ride from South Boulder, Louisville, or Superior.

Detailed Description
Dirty South is a 22 mile popular easy route located near Boulder Colorado. This mountain bike only route can be used both directions and has a moderate overall physical rating. This route includes 24 trails. This route climbs 1,627 ft with a max elevation of 6,241 ft then descends -1,628 ft.
Local Trail Association
Local trail association
Boulder Mountainbike Alliance (bouldermountainbike.org)
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Details

More Stats for Dirty South mountain bike route
  • Avg time
    2 hr 49 min
  • Altitude min
    5,521 ft
  • Altitude start
    5,568 ft
  • Altitude end
    5,568 ft
  • Grade
    -0%
  • Grade max
    -30.6%
  • Grade min
    31.7%
  • Distance climb
    11 miles
  • Distance down
    9 miles
  • Distance flat
    3 miles
Avg: 4 (2 votes)
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Trail Conditions
  • Unknown
  • Snow Groomed
  • Snow Packed
  • Snow Covered
  • Snow Cover Partial
  • Freeze/thaw Cycle
  • Icy
  • Prevalent Mud
  • Wet
  • Variable
  • Ideal
  • Dry
  • Very Dry
Trail Flow (Ridden Direction)
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The colour categories are based on what percentage of riders are riding a trail in its intended direction.
  • > 96%
  • > 90%
  • > 80%
  • > 70%
  • > 50%
  • < 50%
  • bi-directional trail
  • no data
Trail Last Ridden
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  • < 1 week
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Trail Ridden Direction
The intended direction a trail should be ridden.
  • Downhill Only
  • Downhill Primary
  • Both Directions
  • Uphill Primary
  • Uphill Only
  • One Direction
Contribute Details
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Trail Popularity ?
Trailforks scans ridelogs to determine which trails are ridden the most in the last 9 months. Trails are compared with nearby trails in the same city region with a possible 25 colour shades. Think of this as a heatmap, more rides = more kinetic energy = warmer colors.
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Radar Time
x Activity Recordings
Trailforks users anonymized public ridelogs from the past 6 months.
  • mountain biking recent
  • mountain biking (>6 month)
  • hiking (1 year)
  • moto (1 year)
Activity Recordings
Trailforks users anonymized public skilogs from the past 12 months.
  • Downhill Ski
  • Backcountry Ski
  • Nordic Ski
  • Snowmobile
Winter Trails
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Recent Trail Reports Along Route

statustraildateconditiondescription
Marshall Valley
Oct 8, 2024 @ 7:06pm
2 days
Clear and dry!
Mayhoffer Singletree (City)
Oct 8, 2024 @ 7:06pm
2 days
Clear and dry!
Coal Seam
Sep 27, 2024 @ 6:03pm
Sep 27, 2024
reporter
Community Ditch - West
Sep 18, 2024 @ 6:55am
Sep 18, 2024
Springbrook Connector
Sep 18, 2024 @ 6:55am
Sep 18, 2024
more reports »
  • By LucyJuice & contributors
  • #11994 - 2,471 views