Upcoming Races Near Boulder, CO - Matching: Trail Races

Name: Summer Splash Prairie Dog Half, 10k, & 5k
Start: 2026-07-18
End: 2026-07-18
Location: Castle Rock

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Calarat Challenge Trail Running Festival

Jamestown, CO

Saturday, August 30th, 2025

Half

10K

Trail

View details for race Calarat Challenge Trail Running Festival

Black Squirrel Half Marathon

Bellvue, CO

Saturday, September 6th, 2025

Half

Trail

View details for race Black Squirrel Half Marathon

HRCA Wildcat Mountain Trail Races

Littleton, CO

Saturday, September 6th, 2025

10 Miles

10K

Trail

View details for race HRCA Wildcat Mountain Trail Races

Cirque Series - Arapahoe Basin, CO

Keystone, CO

Saturday, September 6th, 2025

Trail

View details for race Cirque Series - Arapahoe Basin, CO

RexRun For PAWSitivity 2025 5K Trail Run/Walk

Aurora, CO

Saturday, September 6th, 2025

1 Mile

Trail

View details for race RexRun For PAWSitivity 2025 5K Trail Run/Walk

All-Out Fall Fest

Westminster, CO

Saturday, September 13th, 2025

Half

10K

Trail

View details for race All-Out Fall Fest

Estes Epic

Estes Park, CO

Saturday, September 27th, 2025

Ultra

Trail

View details for race Estes Epic

RunAbilities FUN Walk/Run/Roll

Parker, CO

Saturday, October 4th, 2025

Trail

View details for race RunAbilities FUN Walk/Run/Roll

Windsor Marathon, Half Marathon, 10k, 5k & 1 Mi...

Windsor, CO

Sunday, October 5th, 2025

Marathon

Half

10K

Trail

View details for race Windsor Marathon, Half Marathon, 10k, 5k & 1 Mile Run

Suffer Better 9th Annual Fall Trail Runs

Pine, CO

Saturday, October 11th, 2025

Ultra

Trail

View details for race Suffer Better 9th Annual Fall Trail Runs

Blue Sky Trail Marathon & Half Marathon

Fort Collins, CO

Saturday, October 18th, 2025

Trail

View details for race Blue Sky Trail Marathon & Half Marathon

The Great Trailhead Foot Race 10 Miler & 5k

Lakewood, CO

Saturday, October 18th, 2025

10 Miles

Trail

View details for race The Great Trailhead Foot Race 10 Miler & 5k

2025 Eerie Erie

Erie, CO

Saturday, October 25th, 2025

10K

Trail

View details for race 2025 Eerie Erie

All-Out Kooky-Spooky

Golden, CO

Sunday, November 2nd, 2025

Half

10K

Trail

View details for race All-Out Kooky-Spooky

Girls on the Run Northern Colorado Fall 5K

Fort Collins, CO

Sunday, November 2nd, 2025

Trail

View details for race Girls on the Run Northern Colorado Fall 5K

HRCA Backcountry Wilderness Half Marathon

Lone Tree, CO

Saturday, November 8th, 2025

Half

Trail

View details for race HRCA Backcountry Wilderness Half Marathon

Mountain Madness Fall Frenzy Orienteering Trail...

Golden, CO

Sunday, November 9th, 2025

Trail

View details for race Mountain Madness Fall Frenzy Orienteering Trail Race

10k Turkey Trek & 5k Turkey Trot - Now With HAL...

Arvada, CO

Saturday, November 22nd, 2025

Half

10K

Trail

View details for race 10k Turkey Trek & 5k Turkey Trot - Now With HALF MARATHON DISTANCE!

2025 Loveland Turkey Trot

Loveland, CO

Thursday, November 27th, 2025

Trail

View details for race 2025 Loveland Turkey Trot

Sawmill Trail Runs

Pine, CO

Saturday, December 6th, 2025

Trail

View details for race Sawmill Trail Runs

All-Out Fa La La

Westminster, CO

Saturday, December 6th, 2025

Half

10K

Trail

View details for race All-Out Fa La La

Santa Catch 5k & 10k

Windsor, CO

Saturday, December 13th, 2025

10K

1 Mile

Trail

View details for race Santa Catch 5k & 10k

Resolute Runner 5k

Arvada, CO

Thursday, January 1st, 2026

Trail

View details for race Resolute Runner 5k

All-Out Polar Prowl

Arvada, CO

Saturday, January 10th, 2026

Half

10K

Trail

View details for race All-Out Polar Prowl

All-Out Mardi Crawl

Arvada, CO

Sunday, February 22nd, 2026

Half

10K

Trail

View details for race All-Out Mardi Crawl

Lucky Brew Race 5K, 10K, and 15K

Windsor, CO

Saturday, March 21st, 2026

10K

15K

Trail

View details for race Lucky Brew Race 5K, 10K, and 15K

All-Out Spring Fever

Golden, CO

Sunday, March 22nd, 2026

Half

10K

Trail

View details for race All-Out Spring Fever

Run the Ranch

Loveland, CO

Friday, April 10th, 2026

10K

Trail

View details for race Run the Ranch

Platte River Half-Marathon and Relay

Littleton, CO

Sunday, April 12th, 2026

Half

Trail

View details for race Platte River Half-Marathon and Relay

Great Western Trail Race

Severance, CO

Saturday, April 18th, 2026

10K

Half

Trail

Fast

View details for race Great Western Trail Race

All-Out Beat the Heat

Westminster, CO

Saturday, April 18th, 2026

Half

10K

Trail

View details for race All-Out Beat the Heat

Horsetooth Half Marathon

Fort Collins, CO

Sunday, April 19th, 2026

Half

Trail

Fast

View details for race Horsetooth Half Marathon

Summits Trail Runs

Granby, CO

Saturday, June 6th, 2026

10K

12K

Trail

View details for race Summits Trail Runs

Colorado 13er (Half Marathon/10k/5k)

Louisville, CO

Sunday, June 7th, 2026

Half

10K

Trail

View details for race Colorado 13er (Half Marathon/10k/5k)

All-Out Summer Breeze

Arvada, CO

Saturday, June 13th, 2026

Half

10K

Trail

View details for race All-Out Summer Breeze

All-Out Dog Days

Westminster, CO

Saturday, July 11th, 2026

Half

10K

Trail

View details for race All-Out Dog Days

Summer Splash Prairie Dog Half, 10k, & 5k

Castle Rock, CO

Saturday, July 18th, 2026

Half

10K

Trail

View details for race Summer Splash Prairie Dog Half, 10k, & 5k

Explore more in Boulder, CO

Distances:

5K 10K Half Marathon Marathon

Months:

August September October

Tags:

Trail Boston Qualifiers Fast Courses

State:

All Colorado races

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