Runners follow a nearly all-downhill point-to-point route at Colorado’s Slacker Half Marathon, whose claim to fame is that it’s the highest downhill half marathon anywhere in the country. The course starts near the intersection of Loveland Pass Road and Interstate 70 just west of Georgetown, and runners follow the route as it descends from a starting line elevation of about 10,630 feet above sea level to roughly 8,400 feet by the time they reach the race finish line.
(MORE: Slacker Half Marathon event details)