[race_calendar_title]
May 30, 2026
100-500 runners
[get_race_listing_state_city post_id="90986"]
May 16, 2026
100-500 runners
[get_race_listing_state_city post_id="122496"]
June 21, 2026
100-500 runners
[get_race_listing_state_city post_id="122634"]
Slacker Half Marathon
June 20, 2026
1,000-10,000 runners
[get_race_listing_state_city post_id="122687"]
Steamworks Half Marathon logo
June 6, 2026
100-500 runners
[get_race_listing_state_city post_id="89956"]
Elevated Dental Logo
August 22, 2026
500-1000 runners
[get_race_listing_state_city post_id="150578"]
Boulder Rez Marathon logo
August 15, 2026
100-500 runners
[get_race_listing_state_city post_id="150543"]
WILD Wahatoya Runs Logo
September 26, 2026
100-500 runners
[get_race_listing_state_city post_id="150597"]
Deep Creek Trail Half Marathon
September 26, 2026
1-100 runners
[get_race_listing_state_city post_id="123081"]
Black Squirrel Half Marathon logo
September 12, 2026
100-500 runners
[get_race_listing_state_city post_id="122651"]
September 13, 2026
1-100 runners
[get_race_listing_state_city post_id="122621"]
September 12, 2026
100-500 runners
[get_race_listing_state_city post_id="122525"]
October 10, 2026
1-100 runners
[get_race_listing_state_city post_id="122649"]
Rim Rock Run Marathon & Half Marathon logo
November 1, 2026
100-500 runners
[get_race_listing_state_city post_id="122695"]
November 21, 2026
1-100 runners
[get_race_listing_state_city post_id="122579"]
Colorado 24 Hour Run logo
November 1, 2026
100-500 runners
[get_race_listing_state_city post_id="153607"]
December 5, 2026
1-100 runners
[get_race_listing_state_city post_id="123114"]
May 9, 2026
100-500 runners
[get_race_listing_state_city post_id="153617"]
May 9, 2026
100-500 runners
[get_race_listing_state_city post_id="122641"]
Staunton Rocks! Marathon & Half logo
August 22, 2026
100-500 runners
[get_race_listing_state_city post_id="122908"]
[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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