Found 39 races near Boulder

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JUN
13

Arvada, CO
• 23.8 miles
$40 -$85
Join us for our 14th annual Summer Breeze, benefiting the Food Bank of the Rockies! This event features 5K, 10K, and Half Marathon courses that meander along the Van Bibber Creek Trail, offering...
5K 10K Half Marathon
526
JUN
20

Windsor, CO
• 12.2 miles
$15 -$130
Family-friendly fun in Windsor welcoming runners and walkers of all ages
1m 5K 10K Half Marathon
297
JUN
27

Georgetown, CO
• 31.2 miles
$35 -$150
$55.55 New Year’s Eve Pricing The gnome picked the number.New beginnings, big changes, zero regrets.   Hey Beautiful Slackers!   The 2026 Slacker Races will be held on June 27  Start Time...
4m Half Marathon
42
JUL
4

Castle Rock, CO
• 26.9 miles
$43 -$55
Please visit our official race website at www.runtochangelives.org for more registration options.
1K 5K Half Marathon
4
JUL
11

Westminster, CO
• 48.7 miles
$35 -$85
Get ready for a sun-soaked adventure and a fantastic mid-season challenge with our 13th Annual Dog Days 5K, 10K & Half Marathon, benefiting Do Over Dogs! Held in a central location between Denver...
5K 10K Half Marathon
173
JUL
11

Littleton, CO
• 50.6 miles
$17 -$85
Join us for the Heatwave Half Marathon, 10K, & 5K!A sun-soaked summer challenge that’s perfect for the whole family. The fun includes – Great Swag – designer shirt & custom medalChip-timing with...
1m 5K 10K Half Marathon
47
JUL
18

Castle Rock, CO
• 61.4 miles
$40 -$95
Join runners in Castle Rock for this half marathon.
5K 10K Half Marathon
297
AUG
7

Fort Collins, CO
• 0.2 miles
$27 -$110
Friday, August 7th, 2026 Jane Welzel Mountain Ave Mile Faster than Flat - point-to-point, slightly downhill mile on Mountain Avenue in Fort Collins, CO. Featuring multiple race waves:  Mountain...
5K 10K Half Marathon
15
AUG
8

Arvada, CO
• 35.4 miles
$40 -$353
12th annual end-of-summer celebration on Ralston Creek Trail with Half Marathon, 10K, and 5K distances. Official BOLDERBoulder qualifier supporting veterans.
5K 10K Half Marathon
193
AUG
15

Centennial, CO
• 46.2 miles
$30 -$45
🥯🏃‍♂️ Run for the carbs. Stay for the bagels.Love running? Love bagels? This one’s for you.Whether you’re chasing a workout or just here for the carbs, this run is all about balance, fun, and...
1m 5K 10K Half Marathon
28
AUG
16

Erie, CO
• 36.6 miles
$45 -$85
5K road featuring competitive racing and community celebration
5K Half Marathon
134
AUG
22

Fraser, CO
• 58.6 miles
$60 -$85
Push your limits with these stunning, remote races in the heart of the Rocky Mountains - located just 60 miles outsid...
5K Half Marathon
83
AUG
22

Pine, CO
• 26.3 miles
$110 -$130
Welcome to the Staunton Rocks! Marathon & Half, an event put on by trail runners for trail runners. Touring the renowned singletrack of Staunton State Park in Colorado’s Front Range Mountains...
Half Marathon Marathon
60
AUG
22

Evergreen, CO
• 16.8 miles
DescriptionCome run with us in beautiful Evergreen to the top of Bergen Peak at gorgeous Elk Meadow Park!This race day will offer a Half Marathon distance. The Half Marathon will take you to the...
Half Marathon Marathon
23
AUG
23

Westminster, CO
• 48.0 miles
$40 -$95
Welcome to the Pioneer Prairie Dog Half Marathon event; the one that started the series! With 10k and 5k events too!  Everyone is back to school and slipping into a routine.  Make this your...
5K 10K Half Marathon
285
AUG
29

Centennial, CO
• 46.2 miles
$30 -$45
🎀 Join the Fight: Breast Cancer Run! 🎀Lace up and make a difference at our annual Breast Cancer Run! Together, we can raise awareness and funds to support those affected by breast cancer. Enjoy a...
1m 5K 10K Half Marathon
21
SEP
7

Parker, CO
• 46.2 miles
$33 -$85
Celebrate the last blast of summer at the Labor Day Half Marathon
5K 10K Half Marathon
76
SEP
12

Bellvue, CO
• 5.4 miles
$110 -$125
The Black Squirrel Half Marathon will take place on the wonderful trails of Lory State Park to the northeast of Fort Collins, Colorado. The half marathon course offers a tour of the outer...
Half Marathon
29
SEP
19

Buena Vista, CO
• 37.5 miles
$30 -$100
Annual run in Buena Vista with supportive community atmosphere and race day excitement
5K 10K Half Marathon
266
SEP
19

Westminster, CO
• 48.7 miles
$25 -$85
One of Colorado's favorite trails meets one of its most glorious parks at our 9th annual Fallfest! As courses wind southwest along Big Dry Creek Trail, the remarkable sight of Standley Lake with...
5K 10K Half Marathon
305