Colorado trails · Mount Sopris Trail
A 6.7-mile out-and-back in Colorado, with 4,264 ft of climbing, topping out at 12,901 ft. Reaches Thomas Lakes and other lake/summit destinations. Managed by USFS Aspen-Sopris Ranger District.
Most of the climbing sits in the final third — 58% of the ascent, between mile 4.5 and mile 6.7. It climbs almost continuously, with little descent to recover on.
Thomas Lakes Trailhead — parking nearby, restroom. 39.30399, -107.12468 · directions
On August 31, 2026 — the day this page was generated — first light reaches this trailhead at 6:08 a.m., the sun rises at 6:35 a.m. and sets at 7:41 p.m., and the last usable light fades about 8:08 p.m. (MDT) — 13 h 05 min of daylight. At about 2.7 mph plus 30 minutes per 1,000 feet of climbing, the 13.4-mile round trip takes roughly 9 h 14 min, so leaving the trailhead at sunrise puts you back around 3:49 p.m. — 3 h 52 min before sunset.