Big Sky Marathon
Typically 51–80°F · low rain risk
See last 10 years
On this date: rain 0 of the last 10 years
2026
56–89°F
dry
2025
50–70°F
dry
2024
55–91°F
dry
2023
51–80°F
dry
2022
49–73°F
dry
2021
51–88°F
dry
2020
50–82°F
dry
2019
50–82°F
dry
2018
56–74°F
dry
2017
50–76°F
dry
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About this race
The Big Sky Marathon is a high-altitude, downhill quad-burner that descends the Gravelly mountain range en route to the Blue-Ribbon Madison River. Racers log a total descent of nearly 4,900 feet at finish, and a net descent of over 3,800 feet. The inaugural year was 2015, and the BSM has quickly become our most popular test. Ninety-six percent (96%) of the trek is on unpaved, packed and loose gravel.
WE HAVE IMPROVED THE COURSE FOR 2027, ELIMINATING THE OUT AND BACK LOOP TO/FROM HIGHWAY 287, AND THAT COURSE IS NOW PUBLIC ON GARMIN: https://connect.garmin.com/app/course/506792996
And, the half marathon option: https://connect.garmin.com/app/course/506794019
Or, supersize your day with 50K: https://connect.garmin.com/app/course/507504785
Prizes are awarded to the first and second place male and female finishers. Please stay for the after-party at Varney Bridge while Ultra 50K, full marathon, and half marathon registrants all commiserate together over local brews and bites.
Course map
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