Leadville Trail 100

The course is deceptively simple in structure: an out-and-back from Leadville to the turnaround at Winfield, crossing Hope Pass in both directions. What makes it relentless is the altitude. Starting at 10,152 feet in the old mining town of Leadville — the highest incorporated city in North America — runners are already at the limit where altitude begins to significantly affect performance. The first 40 miles follow a mix of road, jeep track, and trail along the valley floor before the course turns toward Twin Lakes and the base of Hope Pass. The climb over Hope Pass (12,600 ft) is the crux of the race, made more memorable by the llamas that packtrain supplies to the Hopeless aid station on the far side. After the turnaround at Winfield, runners face Hope Pass again, this time in the dark for many, before the long return to Leadville. The course is less technical than other Colorado hundreds but the altitude is unrelenting. Runners who live at sea level should plan for significant acclimatization time. The Leadville Trail 100 holds a special place in ultrarunning history — it helped establish the sport in America and its sub-25-hour and sub-30-hour belt buckles remain coveted achievements.