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Ultras · US · WY

Bighorn Trail Run 100 Mile

Ran · this year's race is done.
The 100 mile started at 9 AM on Friday 19 June at Tongue River Canyon and ran to the 8 PM Saturday cutoff at Scott Bicentennial Park in Dayton. Results are posted for all four distances.
Race dateJune 19-20, 2026
Duration2 days
Start9:00am
When82 days ago
First held2002
Free, and always will be. NavRun makes money from race-day planning for runners who want it, never from this. Ultras change constantly, sometimes the morning of. Always confirm with the race director and the official website before you rely on anything here.
Distance 100M
Climb 20,500 ft
Descent 20,750 ft
High point 8,800 ft
Time limit 35:00:00
Aid stations 25
Started not checked yet
Finished 173
Finish rate not checked yet
The course

Where it goes out and back · 25 aid stations · rust marks a stop your crew can reach

Course line from the race's own GPX. Source file.

One hundred miles out and back through the Bighorn National Forest, from Tongue River Canyon up to Jaws Trailhead at 8,800 feet and down again into Dayton. The climb out of the canyon comes in the first eight miles, the long descent to Sally's Footbridge at mile 30 is followed by eighteen miles of climbing to the turnaround, and the climb back out of the canyon from mile 66 to Dry Fork at mile 82.5 is the one runners talk about. The last five miles are gravel road into town.

The race calls the course remote and technical: 76 miles of it is singletrack, and long stretches of eighteen miles of trail are the only way in or out of the back country. Expect steep climbs, long descents, deep mud, creek crossings and mountain weather that changes through the day and night. The medical page warns that altitude above 7,000 feet plus hard effort can bring on altitude sickness, and the course spends much of its middle above that. Runners share the trail with elk, deer, moose, black bear, mountain lions, and rattlesnakes at the lower elevations.

The race

What this one is

The Bighorn 100 runs out and back through the Little Bighorn and Tongue River country of the Bighorn National Forest, starting on Tongue River Canyon Road outside Dayton, Wyoming and finishing in Scott Bicentennial Park in the middle of town. Runners have 35 hours for about 20,500 feet of climbing and 20,750 feet of descent, over 76 miles of technical singletrack, 16 miles of jeep trail and 8 miles of gravel road, with the turnaround at Jaws Trailhead at 8,800 feet. Aid stations sit far apart and deep in the back country: supplies for Lower Sheep Creek and Bear Camp are packed in by horse and mule. The race's own answer to whether there will be mud is yes.

The Bighorn runs began in 1993 as a 50 mile, 50K and 30K, started by local trail runners who wanted people to see the Dry Fork and Little Bighorn River canyons while a pump storage hydroelectric scheme, the Dry Fork Project, was being considered for them. The project was shelved. The 100 mile was added in 2002, on the tenth anniversary of the shorter runs. The race is still put on by trail running volunteers from the Sheridan community, and it has moved to contingency courses in heavy snow years: in 2008 there was four to five feet of snow at Porcupine Ranger Station a week before the race and the 52 and 100 mile courses were redesigned in less than a week.

Getting in

Getting in Entry, lottery and what the race asks of you before race day.

Lottery
No bighorntrailrun.com
Lottery opens
not checked yet
Lottery draw
not checked yet
Field cap
not checked yet
Registration
Other bighorntrailrun.com
Qualifying
not checked yet
Minimum age
not checked yet
Transfers
No bighorntrailrun.com
Deferrals
No bighorntrailrun.com
Crew access, pacers and drop bags

The rules that shape your day Anything marked "not checked yet" is a gap in what we hold, never a no from the race.

Crew allowed
Yes bighorntrailrun.com
Vehicles per runner
1 bighorntrailrun.com
Pacers
Yes, from mile 30.00 bighorntrailrun.com
Muling
Not allowed bighorntrailrun.com
Drop bags
Yes img1.wsimg.com
Cupless
Yes bighorntrailrun.com
Course marking
Fully Marked bighorntrailrun.com
Night running
Yes img1.wsimg.com
Dogs
Not allowed bighorntrailrun.com
Headphones
not checked yet
Crew rules
Crew may meet a runner at Dry Fork Ridge, Sally's Footbridge and Jaws Trailhead, at Camp Creek Ridge on the way out at mile 12.25, where the course crosses Devil's Canyon Road at miles 47 and 49, and from the Tongue River Trailhead to the finish on foot or by bike. One vehicle per runner at each crew point. One crew member may be inside the aid station tent at Dry Fork, Sally's and Jaws, and the rest wait outside; the announcements page puts crewing within 100 feet of the aid station and the course rules within a 100 yard radius. Bring warm clothes: crews are told to expect to wait in freezing temperatures at Jaws and Sally's. No race vehicle may use Tongue Canyon Road after noon on the Friday, and a crew that drives it gets their runner disqualified. Runners are responsible for what their crew does, including driving and parking. bighorntrailrun.com
Pacer rules
Pacers are for the 100 mile only, and one at a time. A pacer may join at Sally's Footbridge outbound at mile 30, at Jaws Trailhead, at Sally's Footbridge inbound at mile 66 or at Dry Fork Ridge inbound at mile 82.5. A runner over 60, or with a medical condition cleared by the race director in advance, may be paced from the start. There is no limit on how many pacers a runner uses across the day. Pacers must be 18, must sign a waiver, must wear the runner's pacer bib, must check in and out of every aid station with their runner, and must carry their own food and drink: the aid stations are stocked for entrants. No physical or mechanical assistance, which the race calls muling. bighorntrailrun.com
Drop bag rules
Drop bags are allowed for the 100, 52 and 32 mile races, at Dry Fork Ridge, Sally's Footbridge and Jaws Trailhead. There is no size limit but no coolers, tubs or buckets: every bag must be soft sided so it fits on the cargo trailers. The race provides the tags and tape at drop-off. Line bags with a plastic sack, because they can sit out in a thunderstorm or a snow storm. Unclaimed bags are taken to Innominate Coffee House and Bakery in Ranchester and can be picked up there on the Sunday morning. img1.wsimg.com
Cutoff philosophy
Thirty five hours works out at an average of 2.94 miles an hour. The cutoffs are taken at check-out rather than check-in, and the race says they do not move: "All cut-off times will be strictly enforced. Runners must be checked OUT of the checkpoint by the cut-off time. Cut-off times will NOT be adjusted for any reason once the 100 mile is in progress (9 am on Friday)." bighorntrailrun.com
Aid stations

Every stop, and what you get there ● yes   · no   ? nobody has checked   – does not apply to this race

Mile Station Cutoff Crew access Bag Pacer Med To next
0.00 Start - Tongue Canyon Road
4,275 ft
? ? · ? 1.25
1.25 Tongue River Trailhead
4,240 ft
? · ? · ? 2.25
3.50 Lower Sheep Creek
5,025 ft
? · ? · ? 5.00
8.50 Upper Sheep Creek
7,450 ft
? · ? · ? 3.75
12.25 Camp Creek Ridge crew point ? ? · ? 1.25
13.50 Dry Fork Ridge
7,480 ft
3:00pm · ? 6.00
19.50 Kern's Cow Camp
6,600 ft
? · ? · ? 7.00
26.50 Bear Camp
6,800 ft
? · ? · ? 3.50
30.00 Sally's Footbridge
4,590 ft
8:30pm 3.50
33.50 Cathedral Rock
5,080 ft
? · ? ? ? 6.50
40.00 Spring Marsh
6,920 ft
? · ? ? ? 7.00
47.00 Devil's Canyon Road crossing, outbound ? ? ? ? 1.00
48.00 Jaws Trailhead
8,800 ft
4:00am 1.00
49.00 Devil's Canyon Road crossing, inbound ? ? ? ? 7.00
56.00 Spring Marsh
6,920 ft
? · ? ? ? 6.50
62.50 Cathedral Rock
5,080 ft
? · ? ? ? 3.50
66.00 Sally's Footbridge
4,590 ft
10:00am 3.50
69.50 Bear Camp
6,800 ft
? · ? ? ? 7.00
76.50 Kern's Cow Camp
6,600 ft
? · ? ? ? 6.00
82.50 Dry Fork Ridge
7,480 ft
3:00pm 5.00
87.50 Upper Sheep Creek
7,450 ft
4:30pm · ? ? ? 5.00
92.50 Lower Sheep Creek
5,025 ft
? · ? ? ? 2.30
94.80 Tongue River Trailhead
4,240 ft
6:45pm ? ? ? 3.20
98.00 Home Stretch
4,040 ft
? ? ? ? 2.00
100.00 Scott Park Finish
3,970 ft
8:00pm ? ? ? ?
Driving your crew

Getting your people there 9 stops with directions the race published.

Start - Tongue Canyon Road mile 0.00

To the 100 mile start: The entrance to the Tongue River Canyon Road is on the northeast side of the Tongue River Bridge on Hwy 14 as a driver enters Dayton coming west from Ranchester. Take the Tongue River Canyon Road proceeding upstream on the northeast side of the Tongue River. Go left at a junction approximately 2.5 miles from Dayton and proceed on the Tongue River Canyon Road approximately 1 mile further to the Amsden Fishing Access area in the Tongue River Canyon. The start will occur on the Tongue River Canyon Road by the big cottonwood tree where the road turns toward the north wall of Tongue River Canyon at the west end of the fishing access area.

bighorntrailrun.com
Dry Fork Ridge mile 13.50 90 min drive from the stop before cutoff 3:00pm

To the Head of the Dry Fork (Dry Fork Ridge): Take Hwy 14 from Dayton and proceed up the mountain to Burgess Junction. At Burgess Junction, take a right on Forest Service Road #15 (Dayton Gulch Road) proceeding past Burgess Ranger Station and eventually crossing Fools Creek at approximately 5 miles. Shortly after crossing Fools Creek, take a right on Forest Service Road #168 (Freeze Out Road) and proceed approximately 5 miles to the head of the Dry Fork Aid Station which is located at the intersection of Forest Service Road #149 and Forest Service Road #168 (Freeze Out Road).

Parking. Crew parking is about a quarter of a mile from the aid station. Parking is restricted for the inbound visit on the Saturday.

bighorntrailrun.com
Sally's Footbridge mile 30.00 150 min drive from the stop before cutoff 8:30pm

To Sally's Footbridge Aid Station in the Little Bighorn River Canyon: From Dayton, cross the Tongue River Bridge at the eastern aspect of town and turn north on Wyoming Hwy 343 proceeding 5.2 miles to the intersection of Wyoming Hwy 345 (old US Hwy 87). Turn left on Wyoming Hwy 345 and proceed past Parkman, WY, going into Montana at 5.9 miles where you enter the Crow Indian Reservation and continue on this highway until you reach the Littlehorn Road just south of Wyola, MT, at 15 miles. Turn left on the Littlehorn Road, cross the railroad tracks and proceed west on the Littlehorn Road toward the Bighorn Mountains crossing the Little Bighorn River at 9.7 miles, having the pavement change to gravel at 10.5 miles, crossing the Little Bighorn River at 12 miles, and encountering a cattle guard at a 4-way junction at 15.85 miles. Proceed through the cattle guard, taking this primitive road into the mouth of the Little Bighorn River Canyon. You will ford a creek at 0.45 miles, ford a second creek at 0.6 miles, reenter Wyoming at a primitive sign noting that you are at 45 degrees Latitude, and cross the Little Bighorn River on a bridge at 1.5 miles. Continue on the northern side of the Little Bighorn River where you will encounter an area where we wish crews to park at approximately 2.5 miles. After parking, proceed by foot approximately 3/4 mile distance from the designated parking area up the canyon on the primitive road to reach the Footbridge Aid Station.

Parking. Crew park in the designated area about two and a half miles up the canyon and finish on foot: the crew page gives that walk as three quarters of a mile and the 100 mile page as half a mile. A high clearance vehicle is recommended for the last two miles and carpooling is suggested. Do not block the road or the private bridge to the cabins.

bighorntrailrun.com
Devil's Canyon Road crossing, outbound mile 47.00 150 min drive from the stop before

To Devil's Canyon Road Crossing: Take Hwy 14 from Dayton and proceed up the mountain to Burgess Junction. Take Hwy 14A from Burgess Junction towards Lovell approximately 18.7 miles and turn right on Devil's Canyon Road (previously known as Sheep Mountain Road). Go north approximately 2 to 2.5 miles to where the 100 mile course crosses Devil's Canyon Road.

bighorntrailrun.com
Jaws Trailhead mile 48.00 10 min drive from the stop before cutoff 4:00am

To Jaws Trailhead: Take Hwy 14 from Dayton and proceed up the mountain to Burgess Junction. Take Hwy 14A from Burgess Junction towards Lovell for approximately 20.7 miles to turn right on Forest Service Road #13 which is just prior to the road going to the Medicine Wheel and is just prior to Hwy 14A starting to descend off the mountain. Go on Forest Service Road #13 in a northerly direction proceeding past Porcupine Campground on your left at approximately 1.9 miles. Cross over Porcupine Creek and continue driving past the entrance to the Porcupine Ranger Station. Proceed left up the hill past the entrance to Porcupine Ranger Station for about 1/4 mile where you will turn left into the parking lot for Jaws Trailhead at approximately 2.5 miles.

Parking. Park in the designated areas for crew at Jaws Trailhead or as otherwise directed, keeping the entrance clear for traffic and runners.

bighorntrailrun.com
Devil's Canyon Road crossing, inbound mile 49.00 10 min drive from the stop before

To Devil's Canyon Road Crossing: Take Hwy 14 from Dayton and proceed up the mountain to Burgess Junction. Take Hwy 14A from Burgess Junction towards Lovell approximately 18.7 miles and turn right on Devil's Canyon Road (previously known as Sheep Mountain Road). Go north approximately 2 to 2.5 miles to where the 100 mile course crosses Devil's Canyon Road.

bighorntrailrun.com
Sally's Footbridge mile 66.00 150 min drive from the stop before cutoff 10:00am

To Sally's Footbridge Aid Station in the Little Bighorn River Canyon: From Dayton, cross the Tongue River Bridge at the eastern aspect of town and turn north on Wyoming Hwy 343 proceeding 5.2 miles to the intersection of Wyoming Hwy 345 (old US Hwy 87). Turn left on Wyoming Hwy 345 and proceed past Parkman, WY, going into Montana at 5.9 miles where you enter the Crow Indian Reservation and continue on this highway until you reach the Littlehorn Road just south of Wyola, MT, at 15 miles. Turn left on the Littlehorn Road, cross the railroad tracks and proceed west on the Littlehorn Road toward the Bighorn Mountains crossing the Little Bighorn River at 9.7 miles, having the pavement change to gravel at 10.5 miles, crossing the Little Bighorn River at 12 miles, and encountering a cattle guard at a 4-way junction at 15.85 miles. Proceed through the cattle guard, taking this primitive road into the mouth of the Little Bighorn River Canyon. You will ford a creek at 0.45 miles, ford a second creek at 0.6 miles, reenter Wyoming at a primitive sign noting that you are at 45 degrees Latitude, and cross the Little Bighorn River on a bridge at 1.5 miles. Continue on the northern side of the Little Bighorn River where you will encounter an area where we wish crews to park at approximately 2.5 miles. After parking, proceed by foot approximately 3/4 mile distance from the designated parking area up the canyon on the primitive road to reach the Footbridge Aid Station.

Parking. The same canyon parking area and walk in as on the way out.

bighorntrailrun.com
Dry Fork Ridge mile 82.50 150 min drive from the stop before cutoff 3:00pm

To the Head of the Dry Fork (Dry Fork Ridge): Take Hwy 14 from Dayton and proceed up the mountain to Burgess Junction. At Burgess Junction, take a right on Forest Service Road #15 (Dayton Gulch Road) proceeding past Burgess Ranger Station and eventually crossing Fools Creek at approximately 5 miles. Shortly after crossing Fools Creek, take a right on Forest Service Road #168 (Freeze Out Road) and proceed approximately 5 miles to the head of the Dry Fork Aid Station which is located at the intersection of Forest Service Road #149 and Forest Service Road #168 (Freeze Out Road).

Parking. Crew access to Dry Fork Ridge on the Saturday has parking restrictions.

bighorntrailrun.com
Scott Park Finish mile 100.00 75 min drive from the stop before cutoff 8:00pm

Dry Fork Ridge to Scott Park Finish Area is 1.25 hours by car. Park outside Scott Park; a shuttle runs between Scott Park and the Dayton Community Center from noon to 8 PM.

bighorntrailrun.com
What it looks like out there

Somebody has been out there with a camera the tables say the climb is long. these say what long feels like.

9 people have been out there with a camera or a microphone.

+ 1 more.

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