Boulder
Trail Running Calendar near Boulder 2026-2027
Explore the top trail runs near Boulder for 2026-2027! We've gathered 27 exciting trail runs in the area. Check out our detailed list below to find your next local trail run.
November 2026
Trail races in Louisville, Colorado on November 14, 2026 offering 13.1 miles, 10K and 5K out-and-back courses on dirt trails with aid stations and drop bag service.
A 50K looped ultra near Golden, CO visiting four peaks from Parfet Park with an unmarked, self supported course and no entry fee.
December 2026
A limited 40-runner mountain ascent at Thumb Open Space: repeated 2 km laps with 540 ft gain, poker-chip turnarounds, and patch milestones for 14, 18, and 26 ascents.
Free 2.8 mi festive run in Broomfield that finishes with breakfast at La Belle French Bakery and is open to all ages.
Santa Claus Run in Louisville CO on Dec 12 offers 5k, 10k, a half marathon and a kids race with an expo, festive finish gifts and on-course amenities.
A 10K at the YMCA of the Rockies on December 19, 2026, with trail and paved sections and nearly 1,500 feet of climbing; breakfast and a day pass included.
February 2027
A winter bike rally and trail run in Lyons, Colorado offering multiple run and ride distances plus an afterparty with food, music and saunas.
April 2027
May 2027
Trail races at YMCA of the Rockies on May 22, 2027 featuring 10K, 25K, and a 50K with 6,000 feet of gain on mostly runnable singletrack.
June 2027
A mixed gravel-bike and trail-running festival in Lyons, Colorado on June 6, 2027, featuring races from 100K to 5 miles plus relays, BMX, camping and a concert.
A multi distance race weekend in Estes Park featuring marathon and half marathon point to point courses, a limited trail descent, a 5 mile race, kids events and virtual options.
July 2027
A 69-mile three-loop mountain event near Nederland, Colorado with 18,099 ft of climbing, strict weight classes, mandatory high-altitude kit and GPS verification for awards.
Two Brothers Up and Down in Idaho Springs features steep out and back courses: a 10k with about 1,800 ft ascent and a 5k with about 570 ft.
August 2027
Annual four mile charity run in Eldorado Springs with a scenic out and back course, post-run food and prizes, supporting the Colorado Cancer Foundation.
Mountain trail races in Winter Park Colorado featuring 50K, 21K and 10K courses on alpine singletrack with limited fields and aid stations.
Trail races around Standley Lake in Westminster, Colorado offering five dirt-course distances with aid stations, drop bag access and live split tracking.