About This Race
The High Lonesome 100 stands as one of Colorado's most demanding ultramarathons, carving a challenging loop through the pristine Sawatch Range. At 100 miles with over 23,500 feet of elevation gain, this race pushes runners to their limits while rewarding them with some of the most spectacular high-altitude terrain in the Rocky Mountains. The course reaches a maximum elevation of 13,150 feet, taking runners along portions of the Continental Divide Trail and Colorado Trail through terrain that defines mountain running. With 97% of the course on singletrack trails, runners experience the raw beauty of Colorado's fourteener country while navigating technical sections that demand both physical endurance and mental fortitude. Limited to 250 participants, the High Lonesome maintains an intimate atmosphere despite its epic scope. The 37-hour time limit provides a stern but achievable challenge for experienced mountain ultrarunners, while 16 well-positioned aid stations offer crucial support throughout the demanding loop.
The High Lonesome 100 follows a loop course through the heart of the Sawatch Range, utilizing iconic trail systems including segments of the Continental Divide Trail and Colorado Trail. The route features sustained climbs and technical descents across diverse high-altitude terrain, from dense aspen groves to exposed alpine ridgelines.
Runners face significant elevation challenges with multiple climbs above treeline, including the race's high point at 13,150 feet. The predominantly singletrack course demands technical trail running skills, particularly on rocky descents and exposed sections where weather conditions can change rapidly.
Practical Info
Mid-July conditions typically feature warm days and cool nights, with afternoon thunderstorms common above treeline and temperatures potentially dropping below freezing at higher elevations.
COS - Colorado Springs Airport
Nathrop offers limited lodging options; many runners stay in nearby Salida or Buena Vista which provide more extensive accommodations and dining options.
Best For
Notable Features
The High Lonesome 100 distinguishes itself through its combination of extreme elevation gain and high-altitude exposure, taking runners along some of Colorado's most iconic trail systems. The race's location in the Sawatch Range provides access to pristine wilderness areas typically reserved for backpackers, while the loop format allows for strategic pacing and crew support throughout the challenging course.