Date
Sat Jan 6, 2024 (W)
Sun Jan 14, 2024 (NWF)
Sun Feb 11, 2024
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Sun Feb 18, 2024
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Sun Feb 12, 2023 (NWF)
Sun Feb 19, 2023 (W)
All-Out Mardi Crawl Half Marathon, 10k, 5k, 1 Mile
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Stories Ultra 6 Hour and Half Marathon
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Super Half Marathon & 5k Run/Walk
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Location
Arvada, CO
Louisville, CO
Arvada, CO
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Colorado Springs, CO
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Colorado Springs, CO
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Arvada, CO
Sun Mar 5, 2023 (NWF)
Sat Mar 11, 2023 (W)
Sun Mar 17, 2024 (W)
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Sun Mar 24, 2024 (NWF)
That Dam 13.1 & 5k Crush that Dam
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Run Through Time Marathon, Half Marathon, 2-Mile
All-Out Spring Fever Half Marathon, 10k, 5k, 1 Mile
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Greenwood Village, CO
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Salida, CO
Golden, CO
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Fort Collins, CO
Sun Apr 1, 2023 (W)
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Sat Apr 13, 2024 (W)
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Sun Apr 14, 2024 (NWF)
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Sat Apr 15, 2023 (NWF)
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Sun Apr 14, 2024 (W)
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Sun Apr 14, 2024 (NWF)
Sun Apr 14, 2024 (T)
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Sat Apr 27, 2024
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Sun Apr 30, 2023 (T)
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All-Out Beat the Heat Marathon, Half Marathon, 10k, 5k, 1 Mile
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Platte River Half Marathon & Relay (3 hour time limit)
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BSBC Boulder Rez Half Marathon, 10k, 5k
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Spring Fling Prairie Dog Half Marathon (3.5 hour time limit)
Desert RATS Trail Running Festival Half Marathon (1600 elv gain), 10k
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Runs with Scissors Half Marathon, Marathon, 50k
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Aurora, CO
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Westminster, CO
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Littleton, CO
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Boulder, CO
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Fort Collins, CO
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Arvada, CO
Fruita, CO
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Brighton, CO
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Highlands Ranch, CO
Sun May 5, 2024
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Sat May 13, 2023
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Sat May 18, 2024
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Sat May 11, 2024 (T)
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Sun May 19, 2024
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Sat May 27, 2023
Colorado Marathon, Half Marathon, 10k, 5k
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Endure Trail Runs Half Marathon & 10k
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Valkyrie Trail Race 50k, Marathon Half Marathon, 4mi
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Denver Colfax Marathon & Half Marathon
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Fort Collins, CO
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Firestone, CO
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Divide, CO
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Colorado Springs, CO
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Aurora, CO
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Colorado Springs, CO
Sat Jun 3, 2023
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Sat Jun 1, 2024 (W)
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Sat Jun 3, 2023 (T)
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Sat Jun 3, 2023
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Sat Jun 3, 2023
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Sun Jun 2, 2024
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Sun Jun 2, 2024 (W)
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Sat Jun 8, 2024 (W)
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Sat Jun 10, 2023 (T)
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Sat Jun 10, 2023
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Sun Jun 11, 2023
Sun Jun 16, 2024 (W)
Sat Jun 24, 2023 (W)
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Sat Jun 24, 2023
Runoff Runoff Marathon, Half Marathon, & 6k
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Revel Rockies Marathon & Half Marathon
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Louise Hammond Memorial Beardance Run Half Marathon, 10k, 5k
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Colorado 13er (13.1mi), 10k, 5k
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Steamboat Marathon, Half Marathon & 10K
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All Out Summer Breeze Half Marathon, 10k, 5k, 1 Mile
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Evit's Hope Half Marathon, 5k & Family 1-mile
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Breckenridge Brewery Half Marathon & 5k
Estes Park Marathon, Half Marathon, 10k, 5k
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Creede, CO
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Morrison, CO
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Evergreen, CO
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Basalt, CO
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Towaod, CO
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Louisville, CO
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Steamboat Springs, CO
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Arvada, CO
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Colorado Springs, CO
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Durango, CO
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Littleton, CO
Estes Park, CO
Georgetown, CO
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Westminster, CO
Thu Jul 4, 2024
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Sat Jul 13, 2024 (W)
Sat Jul 15, 2023
Sat Jul 20, 2024 (NWF)
Sat Jul 29, 2023 (T)
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All-Out Dog Days Half Marathon, 10k, 5k, 1 mile
Aspen Valley Marathon, Half Marathon, 5k
Summer Splash Prairie Dog Half Marathon
Longmont, CO
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Westminster, CO
Aspen, CO
Castle Rock, CO
Crested Butte, CO
Sat Aug 3, 2024
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Sat Aug 3, 2024 (W)
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Sat Aug 5, 2023
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Sun Aug 6, 2023 (T)
Sat Aug 12, 2023
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Sat Aug 12, 2023
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Sat Aug 17, 2024 (W)
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Sat Aug 19, 2023
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Sun Aug 18, 2024 (NWF)
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Sat Aug 26, 2023 (T)
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Sat Aug 26, 2023
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Sat Aug 24, 2024 (NWF)
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Sat Aug 26, 2023
Vacation Races Rocky Mountain Half Marathon
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All-Out Runapalooza Half Marathon, 10k, 5k, 1 Mile
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Fort Collins Human Race Half Marathon, 10k, 5k
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The Emerald Mountain Epic Marathon & Half Marathon
Georgetown to Idaho Springs Half Marathon
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Boulder Rez Marathon, 3/4 Marathon, Half Marathon, 10k, Relay
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Dynafit Arrowhead Half Marathon, 10k, 5k
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Louisville Trail Half Marathon, 10k, 5k 2023 Registration
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Staunton Rocks! Marathon & Half Marathon
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TBK Bank "Thirsty 13" Half Marathon
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Estes Park, CO
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Arvada, CO
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Fort Collins, CO
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Steamboat Springs, CO
Georgetown, CO
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Boulder, CO
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Ouray, CO
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Vail, CO
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Erie, CO
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Louisville, CO
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Pine, CO
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Durango, CO
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Fraser, CO
Mon Sep 4, 2023
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Sat Sep 9, 2023 (T)
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Sat Sep 9, 2023
Sat Sep 16, 2023 (W)
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Sun Sep 17, 2023
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Sun Sep 17, 2023 (W)
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Sat Sep 23, 2023 (NWF)
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Sat Sep 23, 2023 (T)
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Sat Sep 23, 2023 (T)
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Sat Sep 23, 2023
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Sun Sep 24, 2023 (T)
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Sat Sep 30, 2023
Labor Day Half Marathon, 10k, 5k
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Ned * Ned Half Marathon, 10k, 5k
All-Out Fallfest Marathon, Half Marathon, 10k, 5k, 1 Mile
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Fall Equinox Marathon, Half Marathon & 5 Mile
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"The Pioneer" Prairie Dog Half Marathon & 10k Westminster
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Snow Mountain Ranch Trail Half Marathon, 10k, 5k
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Beulah Challenge Half Marathon, 10k, 5k Trail Run & Walk
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Bear Chase Trail Half Marathon & 10k
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Colorado Springs Marathon & Half Marathon 10 Year Anniversary
Parker, CO
Fort Collins, CO
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Nederland, CO
Buena Vista, CO
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Brighton, CO
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Fort Collins, CO
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Westminster, CO
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Granby, CO
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Snowmass, CO
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Beulah, CO
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Morrison, CO
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Colorado Springs, CO
Sun Oct 1, 2023
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Mon Oct 2, 2023 (W)
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Sat Oct 7, 2023
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Sun Oct 8, 2023
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Sun Oct 8, 2023
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Sat Oct 14, 2023
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Sat Oct 15, 2022
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Sun Oct 15, 2023 (W)
Sat Oct 28, 2023 (W)
New Belgium Half Marathon & 5k
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Center of the Nation Series Marathon, Half Marathon, 50/10/5k (day 1)
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Breckenridge Road Marathon, Half Marathon & 10k
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Boulderthon Downtown Edition 13.1 & 26.2
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Windsor Marathon, Half Marathon, 10k, 5k
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Long View Marathon & Half Marathon
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Fort Collins, CO
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Sterling, CO
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Breckenridge, CO
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Boulder, CO
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Windsor, CO
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Fort Collins, CO
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Mancos, CO
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Westminster, CO
Golden, CO
Sat Nov 4, 2023 (T)
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Mon Nov 6, 2023 (W)
HRCA Backcountry Wilderness Half Marathon 2023 Registration
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Mainly Marathons Southwest Series 26.2mi, 13.1mi, 50/10/5k (day 2)
Highlands Ranch, CO
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Durango, CO
Sat Dec 2, 2023 (W)
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Sat Dec 9, 2023 (W)
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Sun Dec 3, 2023
All-Out Fa La La Half Marathon, 10k, 5k, 1 Mile
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Four Corners Quad Keyah Colorado Half Marathon
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Westminster, CO
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Ute Mountain, CO
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Pueblo, CO
Colorado Half Marathon Calendar event dates in grey are delinquent dates not updated by the race organizer yet. We strive to have dates 1 year out for Colorado half marathons, but have no control of when they set, announce or update their dates.
The Colorado Half Marathon Calendar is a complete simplistic listing of half marathons in Colorado. Currently the Colorado half marathon schedule has 2023 Colorado half marathons and 2024 Colorado half marathons as they roll in. Colorado half marathons 2023 & Colorado half marathons 2024 also identify trail half marathons and walker friendly half marathons by a (T) symbol and a (W) symbol. The (T) means it is a TRUE trail half marathon (off road, switchbacks, etc) and a (W) means it is truly "official walker friendly" requiring the half marathon to allow a minimum of 18:32 mile pace, minimum 4 hours for participants to finish the 13.1 mile distance.
The Colorado half marathon schedule of course features races such as Rock'n'Roll Denver Marathon and Rock'n'roll Denver Half marathon, along with a complete listing of Colorado half marathons, Denver half marathons, Ft. Collins half marathons, Colorado Springs half marathons, Boulder half marathons, Rocky Mountain half marathons, Vail half marathons, and many more half marathons in Colorado.
A half marathon is 13.1 miles (or in kilometers is a 21k). We understand sometimes there will be a slight margin of error up or down when runners run or walk any race distance, however our calendar only is a listing for true half marathons that do all they can to measure their course as an official half marathon 13.1 mile / 21k distance. Races that are not 13.1 miles, we encourage not to call their race a 1/2 marathon to lessen confusion for runners & walkers looking to participate in a true 1/2 marathon distance. Some runners don't care, but you'd be surprised how many that do.