Carbon Valley Half Marathon

The Carbon Valley Half Marathon takes place in Firestone, Colorado, in early May, with a 5K on the same program. The 13.1-mile course is billed as Colorado at its best, using Firestone and neighboring Frederick as hosts. Runners cover well-kept trails, dirt paths and rural roads on a route that follows the area's mining-town history.

Highlights include Firestone's Central Park and the Firestone Trail, plus a run alongside the lake in Frederick, all with wide views of the Rocky Mountains. The small-town setting comes with big-town services. Colorado weather in spring can switch between sun and snow flurries, and at roughly 5,000 feet of elevation the thinner air is worth respecting.