Trail Running calendar near Nederland 2026-2027

Run along Boulder Reservoir on flat, mostly dirt trail courses with sweeping Rocky Mountain views. Choose from 10K, 3 4 marathon, half, full marathon or relay, with USATF certified courses, a shirt and a finisher medal.

Tackle the sustained climbs and technical trails of Roxborough State Park in this late-summer ultramarathon. Choose between the 50K or 50 mile distance on exposed, challenging terrain. Be prepared for hot conditions, spaced aid, and a manda..

Run the trails around Standley Lake in Westminster, Colorado. Choose from five distances, from a 5K to a 50K, on out-and-back dirt routes. Experience a cupless race with scenic views and a festive atmosphere.

The Leadville Trail 100 Run is a legendary 100-mile ultramarathon in the Colorado Rockies. With over 15,000 feet of elevation gain and a summit over 12,500 feet at Hope Pass, it's a massive high-altitude challenge. Finishers within 30 hours..

Experience the high-altitude scenery of Leadville on this 10K course, which follows the first and final miles of the famous LT100 Run. With a single aid station and awards for top finishers, it's a classic mountain run. Registration is open..

A midweek trail 5k at Lory State Park in Bellvue, Colorado, presented as part of an August series. Chip timing, series points and awards, free vintage shirts for registrants, and pizza and beverages after each race.

A four-race trail series on Tuesday evenings in August in Lory State Park. Distances include 5K, 10K, and 12K routes with varying elevation. Pizza and drinks follow each race, with series awards at the end.

Trail races in Fraser, Colorado on August 22, 2026, offering a Half Marathon and a 5K on unpaved roads and trails. Proceeds support the Shining Stars Foundation and dogs are allowed on leash.

Staunton Rocks! Marathon and Half Marathon This trail running event takes place in Colorado's Front Range Mountains, southwest of Denver, within Staunton State Park. The course tours the park's renowned singletrack trails, passing by histor..

Event Overview The Arrowhead Half Marathon & 5K is a trail running event held in Arrowhead, Colorado, as part of the Vail Trail Running Series. The event features two race distances: a half marathon (21.4K / 13.3 miles) and a 5K (5.6K /..

Event Overview The Lory Summer Trail Series consists of four midweek trail races held on Tuesdays in August at Lory State Park near Bellvue, Colorado. Each race is a separate event with a different distance and course profile, ranging from..

Trail races on the Miller Park and Ridgeline trails in Castle Rock offering 50K, 25K, 10K and 5K with aid stations, drop bag support, chip timing and live split tracking; proceeds support local open space and trail efforts.

Trail races of 5 mile, 16 mile and 50K on August 29, 2026 in Steamboat Springs. Mountain courses start and finish at Torian Plum Lawn and climb above 10,000 ft with cupless aid stations.

A family-focused trail event at Arapahoe County Fairgrounds on August 29, 2026, featuring a 5K run, a family 5K walk and a kids 1 mile run. The day includes dog demonstrations, a costume contest, auctions, vendors and a pancake breakfast.

Multi day ultrarunning event in Loveland, CO featuring timed and distance races from 50k to 200 miles. Runners use a flat two mile loop at Centennial Park with on site camping, aid station, chip timing, and buckle awards.

A mountain trail race at Arapahoe Basin on September 5, 2026 covering *9.4 miles* and *2,211 ft* of ascent, with Sport, Expert and Pro divisions, a 700 runner cap, on course aid stations and category prizes.

This high-altitude trail run starts at 10,000 feet on Rabbit Ears Pass. The 10k course features 1,200 feet of climbing and descending on a mix of dirt roads and single-track. A shorter 5k option is also available.

A remembrance running event in Longmont, Colorado on September 11 and 12, 2026 featuring loop course races from 5K to 100 miles and a virtual option. The event includes aid stations, participant shirts, finisher awards, and on site food for..

Ned Ned Trail Fest The event is scheduled for September 12, 2026. The event address is 151 East Street in Nederland, Colorado, at an elevation of 8,236 feet. It is organized to support TEENS, Inc., a nonprofit. The organization provides ear..

Snow Mountain Ranch in Granby Colorado features trail races from 5K to 50KM across dirt trails with varied elevation and mountain views. Loop courses include aid stations, drop bag access, onsite lodging, and a pacer option for the 50KM fin..