Colorado in late fall is a funny kind of gift. The summer crowds have thinned, the aspens have done their thing, and the trails and roads settle into that crisp, quiet stretch where a half marathon feels less like a summer obligation and more like a good excuse to get outside. November and December here mean cool starts, honest effort, and finish lines that don't require a medic tent and a prayer.
If you've been circling a late-season race, this is your nudge. There are three upcoming half marathons in Colorado in this window, and each one has its own personality. Here's a look at what's on the calendar so you can plan now, register soon, and give yourself something to train toward as the year winds down.
Rim Rock Marathon and Half Marathon — Sunday, November 1, 2026
Fruita kicks off the stretch with a race that lands right at the turn of the season. Rim Rock is the earliest of the three, which makes it a great target if you want to close out your fall training on a high note before the holiday chaos sets in. Fruita sits on the western edge of the state, and a race there is a reminder that Colorado isn't just Front Range crowds — it's wide-open country with a character all its own. If you like your half marathons with a side of small-town charm and a date that gets you moving early, put this one on your list.
HRCA Backcountry Wilderness Half Marathon — Saturday, November 7, 2026
The HRCA Backcountry Wilderness Half Marathon in Lone Tree is the highest-rated of the bunch, and it's easy to see why it draws attention. A Saturday race in early November gives you a full weekend to enjoy it, and Lone Tree puts you close to the Denver metro without the full downtown shuffle. Whether this is your first half or one of many, a race with this kind of reputation is worth a serious look — it's the kind of event that rewards a little planning and gives you a story to tell afterward.
Rock Canyon Half Marathon — 40th Anniversary Run! — Sunday, December 6, 2026
Pueblo's Rock Canyon Half Marathon closes out the window with a milestone: the 40th anniversary run. There's something special about a race that's been around for four decades — it means generations of runners have toed that line, and you get to add your name to the list. A December date in Pueblo is a nice way to cap the year, and the anniversary angle makes it feel like more than just another race. If you've been looking for a reason to commit to a late-fall goal, this is a good one.
Why Colorado in Late Fall
There's a practical case here, too. November and December races tend to be smaller, calmer, and easier to plan around than the packed spring and summer calendar. You get cooler weather, a cozier start line, and a finish that feels earned. Colorado's range — from the western slope to the Front Range to the southern part of the state — means you can pick a race that fits your travel style and your training timeline.
Training is easier with support, and picking a race is easier when you can see the whole picture. Whether this is your first half or one of many, these three give you a real reason to keep lacing up as the days get shorter.
Find Your Next Colorado Half
Ready to plan? Head to our half marathons in Colorado directory to see every upcoming race in the state, compare your options, and find the one that fits your season. From your first 13.1 to your next adventure, we're in it with you.