Sourdough
Sourdough Trail is a 14.6-mile trail in Arapaho and Roosevelt National Forests, Colorado. The Forest Service rates it trail class 2, moderately developed. It is open to hiking, horse and pack stock and mountain biking.
Trail conditions, closures and hazards are not tracked here. The Arapaho and Roosevelt National Forests official page carries current alerts and closure orders.
Map
One end Other endLine simplified to about 100 metres. Basemap from the USGS National Map.
| One end | 40.0279° N, 105.5249° W · Directions ↗ |
| Other end | 40.1275° N, 105.5179° W · Directions ↗ |
The ends are the two ends of the longest connected chain of segments. The record does not say which is the usual start. The trail is recorded as 4 segments.
The trail
| Length | 14.6 miles |
| Trail class | 2, moderately developed |
| Type | land trail |
| Surface | native material |
| Typical grade | 12-20 percent |
| Typical tread width | 18-24 inches |
| Motor vehicles | Closed to all motorized use year-round |
| Accessibility | Not evaluated |
| Trail numbers | 835 |
| Forest | Arapaho and Roosevelt National Forests (unit 0210) |
| States | Colorado |
| Detail published | management level, with uses |
Values are the set across all segments. Class 1 is minimally developed and class 5 is fully developed. Grade and width are the forest's typical values, not measured extremes.
Weather by month
Allowed uses
| Hiking | Allowed year-round |
| Horse and pack stock | Allowed year-round |
| Mountain biking | Allowed 06/01 to 10/31 (month/day) |
A use is listed when the Forest Service records it as managed, accepted or discouraged on any segment. Discouraged still means legal. Uses marked restricted are left out. Where the forest publishes a Motor Vehicle Use Map, that map governs motorized use.
Trailheads
Sourdough Trailhead No season published Dispersed camping is prohibited within ¼ mile of either side of Rainbow Lakes Road. See Order Motorized vehicles are prohibited. Practice Leave No Trace principles. | under 0.1 mi |
Brainard Lake Gateway Trailhead No season published Pack animals (horses/llamas); recreational shooting (except legal hunting) and being on trails posted as closed is prohibited. Practice Leave No Trace principles. Fishing and hunting are permitted in accordance with regulations established by Colorado Parks & Wildlife. Parking off pavement or in a manner that blocks traffic is prohibited. Overnight parking at the trailhead is permitted, but camping is not allowed. When using Scan & Pay, your vehicle license number will be recorded in our system for that day. All other vehicles must properly display a day use registration receipt or interagency pass during winter operating season. Be sure to take note of other winter regulations and important information when visiting Brainard Lake Gateway Trailhead. | under 0.1 mi |
Red Rock Trailhead No season published Prohibited: Pack animals (horses/llamas); recreational shooting (except for legal hunting) and being on trails posted as closed. Brainard Lake Recreation Area Summer Season (May 1 - Nov 14): Dogs must be on a hand-held leash at all times; dispersed camping is prohibited. When open, camping is only allowed within Pawnee Campground (no camping is permitted in closed campgrounds). Brainard Lake Recreation Area Winter Season (Nov 15 - Apr 30): Motorized vehicles are prohibited; dogs allowed only on the Brainard Lake and Lefthand Park Reservoir Roads; camping is prohibited within 1/4 mile of developed recreation sites except Red Rock Lake. Practice Leave No Trace principles. Fishing and Hunting: Permitted in accordance with regulations established by Colorado Parks & Wildlife. | under 0.1 mi |
Distance is from the point to the nearest part of the trail line. Season text is what the forest wrote and is often a season name rather than a date.
Trails nearby
Camping nearby
Campsite Atlas cards carry site counts and booking links from Recreation.gov. Forest Service cards come from the recreation layer and link the agency page.
Fire nearby
- PrescribedFront Country Broadcast Rx
19 mi from the trail midpoint
- PrescribedSalt Cabin Broadcast Rx
39 mi from the trail midpoint
- PrescribedHarris Park Broadcast Rx
39 mi from the trail midpoint · 390 acres
- PrescribedMagic Feather Broadcast Rx
45 mi from the trail midpoint
Distance is to the reported incident point, not the fire edge. Closure orders are on the forest's official page.
Explore
Park units nearby
Historic places nearby
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Titles come from Open Library's catalog, matched by subject heading or by title.
Reference
Questions people ask
How long is the Sourdough Trail?
The Forest Service records 14.6 miles under this name in Arapaho and Roosevelt National Forests, the sum of 4 segments.
Source: Forest Service trail layer
What is allowed on the Sourdough Trail?
Hiking, horse and pack stock and mountain biking are allowed. The trail is closed to motor vehicles year-round. Some uses are seasonal. The allowed uses section lists the dates.
Source: Forest Service trail layer
Where does the Sourdough Trail start?
The line begins at 40.0279° N, 105.5249° W and ends at 40.1275° N, 105.5179° W. The nearest recorded trailhead is Sourdough Trailhead, under 0.1 miles from the line. The record does not say which end is the usual start.
Source: Forest Service trail layer
Is the Sourdough Trail in a wilderness area?
No. The trail line does not cross any polygon in the National Wilderness Preservation System layer.
Source: Wilderness Connect
Where can I camp near the Sourdough Trail?
Camp Dick (0.2 mi), Peaceful Valley (0.4 mi) and Pawnee Campground (1.2 mi) are within five miles of the trail. The camping section lists all 5 with site counts and booking links.
Source: Campsite Atlas
How developed is the Sourdough Trail?
Trail class 2, which the Forest Service describes as moderately developed. Class 1 is a minimal, unimproved route and class 5 is fully developed, often paved.
Source: Forest Service trail layer
How steep and how wide is the Sourdough Trail?
The typical grade is 12-20 percent. The typical tread is 18-24 inches wide.
Source: Forest Service trail layer
Who manages the Sourdough Trail?
Arapaho and Roosevelt National Forests, Forest Service unit 0210. The trail is in Colorado.
Source: Arapaho and Roosevelt National Forests official page
Is there a fire near the Sourdough Trail?
The interagency feed shows 4 active incidents within 50 miles of the trail midpoint as of 2026-11-01, the nearest Front Country Broadcast Rx at 19 miles. Check the forest's closure orders before you go.
Source: Fire nearby
Source
This page is built from 4 segments named Sourdough in the Forest Service TrailNFS_Publish layer, administrative unit 0210. Wilderness overlap is tested against the National Wilderness Preservation System layer from Wilderness Connect. Trailheads and Forest Service campgrounds come from the Forest Service Recreation Opportunities layer. Data refreshed November 1, 2026. The methodology page explains how segments become trails.