Trail Run Project Logo

An event put on by trail runners for trail runners.

Your Rating: Rating Rating Rating Rating Rating      Clear Rating
Your Difficulty:
Your Favorites: Add To-Do · Your List
Zoom in to see details
Map Key







7,080' 2,158 m


5,444' 1,659 m


10,820' 3,298 m


10,820' 3,298 m



Avg Grade (5°)


Max Grade (30°)

Dogs Leashed

Features Fall Colors · Lake · Views · Wildflowers · Wildlife


Welcome to the fourth running of the Quad Rock 25 and 50 mile trail races, an event put on by trail runners for trail runners.

Taking place on the trails and hills west of Fort Collins in Lory State Park and Horsetooth Mountain Park, the Quad Rock 25/50 will take you on a tour of the Fort Collins skyline, situated on the northeastern boundary of Colorados mighty Rocky Mountains. Look east from the courses high ridges and you'll see the Great Plains extending as far as the eye can see; look west and you'll take in the layered ridgelines and summits of Northern Colorados Rocky Mountain swell, dominated 30 miles away by a towering Longs Peak, the undisputed monarch of Colorados northern Front Range.

We aspire to not only offer a first class trail racing experience on a challenging, scenic, and impeccably marked course, but also a top-notch post-race experience that will leave your bellies full, your feet tapping and your mouths yapping.

The 25-mile loop will take you to the base of two of the more prominent granite outcroppings atop the West Ridge of the Fort Collins skyline by way of the Mill Creek drainage and the Spring Creek Valley. All told, you'll ascend a touch over 5,500 vertical feet on more than 23 miles of premium, gnarled-out singletrack connected by two miles of dirt road. Run the second loop in reverse for a full 50 miles and a net vertical gain in excess of 11,000 feet.

Hang around after your run for live music, barbequed goodness, awesome awards, and some mighty tall tales.

Thats how we roll in The Fort. Welcome!

Need to Know

The 2015 race will begin by following the main park road to the Arthurs Trailhead, giving runners two miles to spread out before hitting the South Valley trail at the east Arthurs trailhead parking (horse) lot. We will also use the new Nomad trail connector from the Lory Park border to Sawmill, as in 2014. The 2015 is the same as 2014, and close to the same distance as the original 2012 course (~50.1 miles) and a half mile shorter per loop than 2013.

Drop bags will be allowed at the Horsetooth Trailhead (Mile 10.3 and 39.5) and the Soldier Canyon finish (Mile 24.9 for the 50 milers). Horsetooth drop bags will not be returned to the finish area until after all 50 milers have cleared the station. If 25 milers need to leave earlier, they may drive to the aid station to pick up their bags.

Runner Notes

The course will be well marked with hot pink flagging tape plus extra pin flags and flour at important intersections. On longer stretches of trail, flagging will be placed approximately every quarter mile. Turns will be marked heavily with 3-4 extra flags before the turn and 3-4 flags within line of sight leading away in the right direction. So if you see a lot of flags, pay attention and watch for the next turn. If you don’t see any flags, you’re off course and need to turn back.

All trails in the park are well marked and the route can be run with a map and the following detailed directions. Any runner should be able to follow the course markings but if you are familiar with the directions below and carry a map, you won’t have any trouble on race day.


The race will start at the gateway to the Soldier Canyon picnic area. Runners will follow the road out of the trailhead and head south on the Lodgepole Drive loop (where runner vehicles are parked) and will continue down the main park road to the Arthurs trailhead.

Take the first left into the Arthurs horse trailer parking lot and head straight onto the east side of the South Valley Loop Trail. Immediately after crossing the park border, turn right onto the Nomad Trail. At the next junction, take another right onto the Sawmill Trail. Continue up Sawmill and take your first left onto the Stout Trail, which will roll south to the Towers service road. Turn right on Towers Road (dirt) and continue up the hill until you reach the aid station.

From the Towers Road aid station, turn left onto the Spring Creek Trail and follow it all the way down the Spring Creek Valley, making a left, and staying on the Spring Creek Trail, at a three-way intersection by the creek at the bottom.

Follow Spring Creek Trail for another half mile, after which the main trail will turn into the Horsetooth Falls Trail and will take you back to the Horsetooth Trailhead aid station, which is also the main parking area for the Horsetooth Mountain Open Space.

From the Horsetooth Trailhead, take the Soderberg Service Road up to the Horsetooth Rock Trail, and turn left, continuing on the foot trail up to the Wathan/Westridge Trail junction. Turn right off of the Horsetooth Rock Trail onto the Wathan Trail and continue straight (stay left) onto the Westridge Trail and follow it north to Towers Road. Take a right on Towers and the aid station will be right around the corner.

From the Towers aid station, take a left on the Mill Creek Trail and follow it all the way back to the Arthurs Trailhead in Lory State Park. Midway down Mill Creek Trail, watch for a sharp left turn at the Loggers junction. Shortly after you enter Lory State Park, the Mill Creek Trail will come to a T junction. Take the right onto the Mill Creek Link Trail and follow that to the South Valley Trail and the Arthurs Rock trailhead.

Start up the Arthurs Rock Trail and about 3/4 of a mile up, take a sharp left to connect to the Howard Trail. Follow Howard all the way up and around the back side of Arthurs Rock. Take a sharp left onto the Timber Trail behind the rock. The first part of Timber is a 4WD logging road. About 3/4 mile down the road, take the 90 degree right turn onto the Timber singletrack trail. Keep left past Well Gulch and follow Timber all the way to the Timber Trail on the valley floor. Exit the Timber trailhead and take the short connector trail back to the Soldier Canyon start/finish.

50 Milers will run the same 25 mile loop in reverse and from the last stop at the Arthurs trailhead runners will stay on the East Valley Trail all the way to the finish area.


Land Manager: Larimer County, Colorado

Shared By:

Tom Robson

Trail Ratings

  4.8 from 5 votes


  4.8 from 5 votes
5 Star
4 Star
3 Star
2 Star
1 Star
Recommended Route Rankings


in Colorado


10 Views Last Month
2,043 Since Apr 2, 2015
Difficult Difficult



Horsetooth Mountain Park, Fort Collins, CO.
Feb 23, 2019 near Bellvue, CO
View of Horsetooth Reservoir from the Timber Trail.
Sep 8, 2019 near Bellvue, CO
Northern Colorado summer wildflowers. This is called "Chiming Bells".
Jul 27, 2019 near Bellvue, CO
View of Horsetooth Rock from about 0.75 miles southeast. This is the trail leading to the top.
Apr 16, 2018 near Bellvue, CO
The beautiful Horsetooth Mountain Park.
Apr 2, 2015 near Laporte, CO
Approaching the Horsetooth Falls
Mar 18, 2019 near Bellvue, CO



Current Trail Conditions

Add Your Check-In


Aug 15, 2020
Michael Reschly
Very challenging 50.3mi — 13h 44m
May 12, 2018
Kritty Levorson
Trails were a muddy mess and the views were clouded by the mist but it still was a fun time and the volunteers were phenomenal. 50mi — 13h 07m
Mar 22, 2018
David Braunlich
May 10, 2014
Chris Rozoff
Only did the "half" 25-mile version. 25.9mi

Join the Community

Create your FREE account today!
Already have an account? Login to close this notice.

Get Started