Upcoming Half Marathon Races Near Boulder County, CO

Name: All-Out Spring Fever
Start: 2027-03-21
End: 2027-03-21
Location: Golden

Bigfoot Half Marathon

Estes Park, CO

Saturday, April 25th, 2026

Featured

Half

View details for race Bigfoot Half Marathon

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NoCo Half Marathon & 10K

Loveland, CO

Saturday, April 25th, 2026

10K

Half

View details for race NoCo Half Marathon & 10K

Runs With Scissors Races

Brighton, CO

Saturday, April 25th, 2026

Half

Marathon

Ultra

View details for race Runs With Scissors Races

Blue Heron Half & 5K

Brighton, CO

Sunday, April 26th, 2026

Half

Fast

View details for race Blue Heron Half & 5K

The Colorado Marathon

Fort Collins, CO

Sunday, May 3rd, 2026

Marathon

Half

10K

View details for race The Colorado Marathon

Longmont Half & 5k (LM Half)

Longmont, CO

Sunday, May 3rd, 2026

Half

View details for race Longmont Half & 5k (LM Half)

Hometown Half Marathon & 5k/10k - Denver

Littleton, CO

Sunday, May 10th, 2026

1 Mile

10K

View details for race Hometown Half Marathon & 5k/10k - Denver

Hometown Half Marathon & 5k/10k - Denver

Denver, CO

Sunday, May 10th, 2026

10K

Half

View details for race Hometown Half Marathon & 5k/10k - Denver

Girls on the Run Rockies Colfax SoleMates 2026

Denver, CO

Sunday, May 17th, 2026

Marathon

Half

View details for race Girls on the Run Rockies Colfax SoleMates 2026

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

Red, White and Brew 5k, 10k & Half Marathon

Windsor, CO

Saturday, June 20th, 2026

10K

Half

View details for race Red, White and Brew 5k, 10k & Half Marathon

All-Out Dog Days

Westminster, CO

Saturday, July 11th, 2026

Half

10K

Trail

View details for race All-Out Dog Days

Heatwave Half Marathon - Denver

Denver, CO

Saturday, July 11th, 2026

1 Mile

10K

View details for race Heatwave Half Marathon - Denver

Bound for Boston Marathon & Half Marathon - Denver

Denver, CO

Sunday, August 2nd, 2026

Marathon

Half

Fast

View details for race Bound for Boston Marathon & Half Marathon - Denver

Choice City Running Festival

Fort Collins, CO

Friday, August 7th, 2026

1 Mile

Half

10K

View details for race Choice City Running Festival

All-Out Runapalooza

Arvada, CO

Saturday, August 8th, 2026

Half

10K

Trail

View details for race All-Out Runapalooza

Erie Half & 5k

Erie, CO

Sunday, August 16th, 2026

Half

View details for race Erie Half & 5k

Byers Peak Stampede Half Marathon & 5K Run

Fraser, CO

Saturday, August 22nd, 2026

Half

Trail

View details for race Byers Peak Stampede Half Marathon & 5K Run

Staunton Rocks! Marathon and Half Marathon

Pine, CO

Saturday, August 22nd, 2026

Marathon

Half

Trail

View details for race Staunton Rocks! Marathon and Half Marathon

Pioneer Prairie Dog Half, 10k & 5k

Westminster, CO

Sunday, August 23rd, 2026

Half

10K

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

Golden Harvest Half Marathon & 5k/10k - Denver

Denver, CO

Saturday, September 5th, 2026

10K

Half

View details for race Golden Harvest Half Marathon & 5k/10k - Denver

Black Squirrel Half Marathon

Bellvue, CO

Saturday, September 12th, 2026

Half

Trail

View details for race Black Squirrel Half Marathon

All-Out Fall Fest

Westminster, CO

Saturday, September 19th, 2026

Half

10K

Trail

View details for race All-Out Fall Fest

Fall Equinox

Fort Collins, CO

Sunday, September 20th, 2026

Half

Fast

View details for race Fall Equinox

Running for Children's Rights to Both Parents -...

Boulder, CO

Sunday, September 27th, 2026

Half

10K

View details for race Running for Children's Rights to Both Parents - 9 of 50 Half Marathons in 50 States

Spooky Sprint - Denver

Denver, CO

Saturday, October 3rd, 2026

1 Mile

10K

View details for race Spooky Sprint - Denver

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

Windsor, CO

Sunday, October 4th, 2026

Marathon

Half

10K

Trail

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

The Long View Marathon

Fort Collins, CO

Saturday, October 10th, 2026

Marathon

Half

View details for race The Long View Marathon

Westy Half & 5k

Westminster, CO

Sunday, October 11th, 2026

Half

View details for race Westy Half & 5k

All-Out Kooky-Spooky

Golden, CO

Sunday, November 1st, 2026

Half

10K

Trail

View details for race All-Out Kooky-Spooky

HRCA Backcountry Wilderness Half Marathon

Lone Tree, CO

Saturday, November 7th, 2026

Half

Trail

View details for race HRCA Backcountry Wilderness Half Marathon

Turkey Trails- Denver

Lakewood, CO

Saturday, November 7th, 2026

1 Mile

10K

View details for race Turkey Trails- Denver

Turkey Trails- Denver

Denver, CO

Saturday, November 7th, 2026

1 Mile

10K

View details for race Turkey Trails- Denver

TURKEY TREK (13.1, 10k, 5k & 2k)

Arvada, CO

Saturday, November 21st, 2026

Half

10K

View details for race TURKEY TREK (13.1, 10k, 5k & 2k)

All-Out Fa La La

Westminster, CO

Saturday, December 5th, 2026

Half

10K

Trail

View details for race All-Out Fa La La

All-Out Polar Prowl

Arvada, CO

Saturday, January 9th, 2027

Half

10K

Trail

View details for race All-Out Polar Prowl

All-Out Mardi Crawl

Arvada, CO

Saturday, February 6th, 2027

Half

10K

Trail

View details for race All-Out Mardi Crawl

All-Out Spring Fever

Golden, CO

Sunday, March 21st, 2027

Half

10K

Trail

View details for race All-Out Spring Fever

Explore more in Boulder County, CO

Distances:

5K 10K Half Marathon Marathon

Months:

April May June

Tags:

Trail Boston Qualifiers Fast Courses

State:

All Colorado races

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