[race_calendar_title]
Valkyrie Trail Race Half Marathon logo
May 9, 2026
1-100 runners
[get_race_listing_state_city post_id="122578"]
Spirit Trail Run Marathon Half Marathon & 8k logo
May 25, 2026
1-100 runners
[get_race_listing_state_city post_id="122523"]
May 3, 2026
500-1000 runners
[get_race_listing_state_city post_id="122654"]
April 25, 2026
1-100 runners
[get_race_listing_state_city post_id="122518"]
April 12, 2026
100-500 runners
[get_race_listing_state_city post_id="122677"]
October 5, 2025
1-100 runners
[get_race_listing_state_city post_id="103702"]
Calarat Challenge Trail Running Festival Half Marathon 10k & 5k
August 31, 2025
1-100 runners
[get_race_listing_state_city post_id="122735"]
July 4, 2025
100-500 runners
[get_race_listing_state_city post_id="122540"]
May 31, 2025
1-100 runners
[get_race_listing_state_city post_id="122510"]
Spring fever logo
March 22, 2026
1-100 runners
[get_race_listing_state_city post_id="103720"]
All-Out Spring Fever logo
March 22, 2026
1-100 runners
[get_race_listing_state_city post_id="122692"]
All-Out Spring Fever logo
March 22, 2026
1-100 runners
[get_race_listing_state_city post_id="122690"]
All-Out Beat the Heat Marathon Half Marathon 10K & 5K logo
April 18, 2026
1-100 runners
[get_race_listing_state_city post_id="123118"]
April 12, 2026
500-1000 runners
[get_race_listing_state_city post_id="122764"]
January 18, 2026
100-500 runners
[get_race_listing_state_city post_id="123111"]
September 14, 2025
1-100 runners
[get_race_listing_state_city post_id="122614"]
Spring Equinox Half Marathon logo
March 23, 2025
1-100 runners
[get_race_listing_state_city post_id="140578"]
June 1, 2024
1,000-10,000 runners
[get_race_listing_state_city post_id="122637"]
Rim to Rim Royal Gorge Races Half Marathon logo
October 4, 2025
1-100 runners
[get_race_listing_state_city post_id="122532"]
August 9, 2025
100-500 runners
[get_race_listing_state_city post_id="122650"]
[hm_paginate_links]

Running in Colorado

FAQ

What are the most popular Colorado half marathons?

The four most popular Colorado half marathons are the Denver Colfax Half Marathon, the REVEL Rockies Half Marathon, the Horsetooth Half Marathon, and Boulderthon.

What’s the best half marathons in Colorado for beginners in 2026?

We have three picks for the best beginner Colorado half marathons. The first is the Slacker Half Marathon for it’s fun fast downhill course. Secondly, Boulderthon, for it’s scenic course, huge crowds, and amazing production quality. And finally, the Denver Colfax Half Marathon for it’s notable and exciting course and race experience.

Which months can I run a half marathon in Colorado?

You can run a half marathon in Colorado in January, February, April, May, June, July, August, September, October, November, and December.

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