Page Type Page Type: Mountain/Rock
Location Lat/Lon: 39.42080°N / 105.6572°W
Additional Information County: Park
Activities Activities: Hiking
Seasons Season: Spring, Summer, Fall, Winter
Additional Information Elevation: 11871 ft / 3618 m
Sign the Climber's Log


Profile photo courtesy of SP member John Kirk.

Foster Benchmark is a quiet, secretive little mountain at the far southeastern end of the Platte River Mountains. Foster sits just above the saddle separating the Platte River Mountains from the Kenosha Mountains and is part of the lovely Lost Creek Wilderness. Concealed from the west by North Twin Cone Peak and South Twin Cone Peak, Foster resides just to the east of these twin twelvers without much fuss or fanfare.
Foster BenchmarkFoster Benchmark.
Photo courtesy of SP member John Kirk

Foster Benchmark is located a good distance from the nearest trailhead and this distance, combined with Foster’s status as an unranked but named benchmark, make it a relatively rarely visited summit. Views from the top are dynamite, however, and include:

Combined with nearby peaks or as a summit objective of its own, a hike up Foster Benchmark makes a good beginner bushwack. Several well-worn rails whisk the hiker close to Foster Benchmark requiring an off-trail tundra hop to the summit. With the exception of a few battles with the dreaded willows, the tundra allows for good visibility of the summit, facilitating off-trail portions of the hike.

Colorado Rank: Unranked
Mountain Range: Platte River Mountains
USGS Quad: Mount Logan
Trails Illustrated Map: #105 (Tarryall Mts / Kenosha Pass)
Rank and Prominence Reference: Lists of John

Getting There

Foster Benchmark is less than five east (as the raven flies) of Kenosha Pass in the Platte River Mountains, in the northeastern corner of Park County. The peak resides in the far northwestern corner of the Lost Creek Wilderness, north of the apex of the Ben Tyler Trail.

Foster Benchmark_Getting There MapClick map image to enlarge

Route Overview

RouteMileageElevation GainSpecial NoteDriving Directions
South Ben Tyler8.5 miles roundtrip2,100 ft.Slightly shorter than North Ben Tyler with less elevation gain, but requires a longer drive to THCO Rd 77 to NW on Co Rd 39 / FS 39; E on FS 56; N FR 133
North Ben Tyler8.8 miles roundtrip3,200 ft.Slightly longer with greater elevation gain than South Ben Tyler, but TH closer to DenverHwy 285 to Shawnee; 2 miles further to parking on S side of Hwy 285

Red Tape

Foster Benchmark lies within the 120,000 acre Lost Creek Wilderness. Wilderness regulations apply, and include, per the Wilderness Act of 1964:
Looking NW toward Guanella PassLooking NW toward Guanella Pass
Kenosha Peak Summit - Twin Cones and BlaineKenosha Peak Summit - Twin Cones and Blaine

  • *Motorized equipment is prohibited, including chain saws, battery powered tools, generators, etc.

  • *Mechanized transportation is prohibited, including, including bicycles, hang gliders or carts.

  • *Aircraft, including helicopters, are prohibited from landing, or dropping off/picking up any materials, supplies or persons.
Please follow LNT (Leave No Trace) principals.

Camping & Lodging

South Twin Cone from Foster BenchmarkSouth Twin Cone from Foster Benchmark


FS 133
Ample rustic 4x4 camping can be found off FS 133 and the spur roads off of it (133a-d). The campsites are dry, so water will need to be hauled in, but the views will be well worth it. With these 4x4 campsites, remember to bring plenty of water, bury human waste and pack out what you packed in.
At the very bottom of the hill near the trailhead there is a nice, large 4x4 accessible campsite along Rock Creek. This campsite is commonly occupied in the warmer months, however, so do not count on this campsite to be available on summer weekends.
SE toward Shawnee and Kenosha MountainsSE toward Shawnee and Kenosha Mountains

South end of Hwy 77
The south end of Hwy 77 (Tarryall Road), near Hwy 24, provides several established U.S. Forest Service camping areas. South Park Ranger District Lake George Area Campgrounds include: Riverside, Spillway, Happy Meadows, Round Mountain, Spruce Grove, and Twin Eagles. Please contact the district office at (719) 836-2031 if you have additional questions about the campground in the South Park Ranger District.

North end of Hwy 77
The north end of Park County 77 and dirt spur roads are abound with off-road campsites. Several campsites off Rt 39 provide views of Mt. Silverheels, Buffalo Peaks, Mount Guyot and other 13ers and 12ers that will bring tears to your eyes.

Cabins, Lodges and Hotels

Numerous cabins can be rented in and around Lake George. There are also a few cabins/lodges along the Tarryall Creek catering especially to the fly fishing visitor. For example: Ute River Ranch. There are a few hotels in Fairplay.

Weather & Seasons

The South Ben Tyler Trail is well-shaded and holds snow later on into Spring than one might expect in this area of drier mountains. Think: Snow, mud, snow, mud, snow, mud… Additionally, a seasonal gate closure at the intersection of FR 56 and FR 39 would make a winter ascent of Foster Benchmark via South Ben Tyler Trail prohibitively arduous for all but the most fiendishly devoted hikers.

The route up and over North Twin Cone is accessible year-round, but would be long one-day snow ascent in the winter and the hiker would have to share a good bulk of the route with jeeps and ATVs in the summer.

Zone Forecast for Jefferson, CO



Children refers to the set of objects that logically fall under a given object. For example, the Aconcagua mountain page is a child of the 'Aconcagua Group' and the 'Seven Summits.' The Aconcagua mountain itself has many routes, photos, and trip reports as children.