Colorado Runner - Colorado's running news, events and results source

Boulderthon, presented by PUMA, has announced new courses for the 2025 running event taking place on Sept. 28. Both the marathon and half marathon routes will take participants on new journeys to some of Boulder’s most popular and highly regarded training routes.

For Colorado runners, missing a run isn’t just a skipped workout; it’s a quiet break in the daily rhythm, one that can stir up frustration, cabin fever, or that creeping fear of losing hard-won fitness.

Get ready to race above it all on Saturday, July 19 at the 5K & 10K@10,000 Feet, the fourth event in the Vail Recreation District's 2025 Vail Trail Running Series. This adventure begins with a scenic gondola ride to Mid-Vail, where you’ll take off on a beautiful alpine course lined with…