The Leadville Trail 100 is an annual ultramarathon held in Leadville, Colorado. This challenging race covers 100 miles of rugged terrain, including high-altitude trails and steep climbs, with an elevation gain of over 15,000 feet. It typically takes place in August and attracts runners from around the world. Participants must complete the race within 30 hours, navigating through various checkpoints along the route. The event is part of the Ultra-Trail World Tour and is known for its breathtaking scenery and demanding conditions, making it a significant challenge for ultrarunners and outdoor enthusiasts alike.