Rio Grande 100

The Rio Grande 100 is an ultramarathon held in South Fork, Colorado, starting and finishing along the Rio Grande River. The challenging 100-mile course traverses the stunning La Garita Mountains, featuring diverse terrain from arid forests to alpine tundra, with four ascents above 12,000 feet. Runners experience scenic trails adorned with golden aspen leaves and rugged rocky sections. Known for its demanding Rocky Mountain environment, the race maintains a friendly, low-key atmosphere appreciated by both participants and their crews. As a late-season event, it often faces snow, prompting enhanced safety measures to ensure the race continues despite harsh weather, making it a uniquely rewarding endurance challenge. Visit the organization's website for the most recent information.