RacesNorthern Rockies
Bighorn 100
Demand
4 out of 5
How much it asks
Worth
4 out of 5
Worth the flight + fee
Dayton, Wyoming, United States
Scorecard · is it worth it?
Worth the flight if the mountains match what you want.
The card
Bighorn is the Wyoming 100 that still talks like a remote mountain event and still is one. The published course is an out-and-back through Little Bighorn and Tongue River country in the Bighorn National Forest: about 20,500 feet of ascent, 76 miles of technical singletrack, jeep and gravel for the rest, 35 hours, a turnaround at Jaws around 8,800 feet. Demand is 4 because that combination of remoteness, singletrack, and weather is a mountain 100. It is not 5 because the altitude is not San Juan-thin and because 35 hours is an honest cutoff rather than a 48-hour siege. June can still put snow on the high trail and heat in the canyon on the same day. That is climate as a dim, not as marketing.
Worth is 4. Destination: people fly to Sheridan or Billings for this, and they should if they wanted a Wild West 100 that is not a Life Time product. The organization's own language is about limited crew, 18-mile stretches, and individual preparation. That is the worth. A 100 that tells you to come self-reliant is rarer than a 100 that sells a expo village. Organization confidence is medium. bighorntrailrun.com publishes aid charts and warnings.
The next date is not yet posted by the RD. If you wanted Colorado, this is the wrong state. If you wanted a Northern Rockies 100 that is actually remote, this is the card next to The Rut's 50K. They are not the same weekend. One is a skyrunning day at a resort. This is a 35-hour out-and-back with bacon at Kern's Cow Camp. Choose honestly. A destination 4 is not an icon. It is a reason to buy the ticket if you wanted this kind of 100.
Who it is for
Self-reliant 100-mile runners who want a remote Wyoming out-and-back with limited crew and real singletrack.
Who should skip
Anyone who needs dense aid and a resort town. Bighorn's own pages tell you to prepare as if the backcountry is the point.
Elevation
Tap or hover for miles, clock, and aidft
Bottom ticks are aid. Longest gap 8.0 mi.
- Start
- 4,101 ft1,250 m
- Finish
- 3,927 ft1,197 m
- Net
- −174 ft−53 m
- Longest climb
- 3,786 ft1,154 m
Start and finish are within 400 ft. Treat net as a loop.
Weekend
Official handbook facts
- Start
- 09:00
- Crew
- 13.5, 30, 48, 66, 82.5 mi
- Drop bags
- 13.5, 30, 48, 66, 82.5 mi
- Pacer from
- 30 mi
Bighorn Trail Run 100 mile aid / course rules · retrieved 2026-09-06 (repo record)
Climate
Typical June at the start area · historical race-week weather
- Typical high
- 76°F (25°C)
- Typical low
- 53°F (12°C)
- Typical precip
- 2.3 in (58 mm) / June
- Days with rain
- 38% of days
- High point
- 8,799 ft (2,682 m)
BewareRain on race weekend in 2 of the last 3 years.
2015–2024 June means at the start / massif. · Open-Meteo ERA5 / climate · retrieved 2026-09-06 (repo record)
Dimensions
Ten 1–5 scores with a one-line why. Organization has a separate confidence tag.
Supporting dimensions · organization confidence medium
Out-and-back 100, 35 hours, Jaws at mile 48. Remote by American 100 standards.
Official about 20,500 ft of ascent. Enough to be a mountain 100.
76 miles of technical singletrack, plus jeep and gravel. The singletrack is the race.
June in the Bighorns: snow possible high, heat in the canyons, storms.
Jaws around 8,800 ft. Real, not Colorado-thin.
Dayton/Tongue Canyon is remote. Crew access is limited on purpose. Come prepared.
A Western classic, not a global final. The field is mountain-serious.
Public aid chart, remote-course warnings. Medium-high from the public record.
A mountain 100 without a circuit tax. Fee not yet sourced.
Little Bighorn and Tongue River country. Wild West is the scenery, not a slogan.
| Dimension | Score | Why |
|---|---|---|
Distance & format How much does the advertised distance and format actually ask? | 4 out of 5 | Out-and-back 100, 35 hours, Jaws at mile 48. Remote by American 100 standards. |
Vertical How serious is the climbing, not just the mile marker? | 4 out of 5 | Official about 20,500 ft of ascent. Enough to be a mountain 100. |
Technicality Hands, poles, route-finding, or just a long dirt road? | 4 out of 5 | 76 miles of technical singletrack, plus jeep and gravel. The singletrack is the race. |
Climate Heat, monsoon, ice, or a friendly summer afternoon? | 4 out of 5 | June in the Bighorns: snow possible high, heat in the canyons, storms. |
Altitude Does the air change the race, or is it a talking point? | 3 out of 5 | Jaws around 8,800 ft. Real, not Colorado-thin. |
Logistics How hard is the weekend around the race: travel, crew, lodging, rules? | 4 out of 5 | Dayton/Tongue Canyon is remote. Crew access is limited on purpose. Come prepared. |
Prestige & field Does the start list and history change what the weekend feels like? | 3 out of 5 | A Western classic, not a global final. The field is mountain-serious. |
Organization From public evidence, does the event look competently run? | 4 out of 5 | Public aid chart, remote-course warnings. Medium-high from the public record. |
Value Entry fee, travel tax, and lottery friction versus what you get on course. | 4 out of 5 | A mountain 100 without a circuit tax. Fee not yet sourced. |
Adventure & scenery Would you fly for the place even if nobody kept score? | 4 out of 5 | Little Bighorn and Tongue River country. Wild West is the scenery, not a slogan. |