Summer Trail Running 2026
266 trail running · 2026/06 – 2026/08
Summer is when the mountains open up. Snowmelt clears high-altitude trails by June, and from then through August, the US trail running calendar peaks with races through terrain that is inaccessible the rest of the year. Western States 100, the most prestigious ultramarathon in the world, sends 369 runners from Squaw Valley to Auburn in late June — 100 miles through the Sierra Nevada in one shot. Leadville Trail 100 follows in August at 10,200 feet above sea level. But summer trail running is not all ultras. 5K and 10K trail races fill every weekend in national forests, state parks, and mountain towns from Vermont to Washington. The heat that makes road running miserable becomes manageable on shaded single track at 6,000 feet. If the pavement is cooking you, the trails are calling.
Upcoming Trail Running
Summer 2026 by the Numbers
Western States Endurance Run (June 27-28, 2026) is the world's oldest 100-mile trail race — 369 lottery slots, thousands apply.
Leadville Trail 100 (August 15-16, 2026) runs at 10,200 feet in Colorado — the "Race Across the Sky."
Summer trail races in the Pacific Northwest, Rocky Mountains, and New England benefit from 14-16 hours of daylight.
Trail running is the fastest-growing segment of distance running — participation doubled between 2018 and 2025.
Why Race in Summer?
Mountain access — high-altitude trails above 8,000 feet are only snow-free from June through September.
Natural cooling — shaded single track at elevation runs 10-20°F cooler than exposed road surfaces at the same latitude.
Premier events — the biggest trail ultras (Western States, Leadville, Hardrock) all run in summer due to mountain conditions.
Daylight training — 14-16 hours of light means pre- and post-work trail runs are possible even on midweek evenings.
Training Periodization
Summer trail race training emphasizes elevation gain over mileage. Replace flat long runs with back-to-back hilly efforts on weekends. Practice power hiking uphills — you will walk the climbs on race day. Break in trail shoes with at least 50 miles before race day.