Running races in or near Boulder, CO
Marathons, 1-milers, 5Ks, half-marathons, 10Ks & more
See below for a frequently-updated, comprehensive list of upcoming running events in the local Boulder, CO area. Races listed here include both walking and running events of various distances — from 1-milers, to 5Ks, to marathons, and everything else in between.
Senior (60+) 5K - Individual Age group/open
Organization: Optimist Club of Erie, Colorado
Date of Race: 10-25-2025
Description: The world-famous Eerie Erie is a Halloweenthemed 5k and ...
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Senior (60+) 10K - Individual Age group/open
Organization: Optimist Club of Erie, Colorado
Date of Race: 10-25-2025
Description: The world-famous Eerie Erie is a Halloweenthemed 5k and ...
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16 and under 10K - Individual Age group/open
Organization: Optimist Club of Erie, Colorado
Date of Race: 10-25-2025
Description: The world-famous Eerie Erie is a Halloweenthemed 5k and ...
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Adult (17+) 5K - Individual Age group/open
Organization: Optimist Club of Erie, Colorado
Date of Race: 10-25-2025
Description: The world-famous Eerie Erie is a Halloweenthemed 5k and ...
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Adult (17+) 10K - Individual Age group/open
Organization: Optimist Club of Erie, Colorado
Date of Race: 10-25-2025
Description: The world-famous Eerie Erie is a Halloweenthemed 5k and ...
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16 and under 5K - Individual Age group/open
Organization: Optimist Club of Erie, Colorado
Date of Race: 10-25-2025
Description: The world-famous Eerie Erie is a Halloweenthemed 5k and ...
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2025 Eerie Erie
Organization: Optimist Club of Erie, Colorado
Date of Race: 10-25-2025
Description: The world-famous Eerie Erie is a Halloweenthemed 5k and ...
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Run with the Buffalo Fun Run: 2.5 Mile ...
Organization: Commerce City Recreation Department
Date of Race: 12-06-2025
Description: DescriptionJoin us for our annual Run with the Buffalo Ugly ...
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Run with the Buffalo Fun Run: 5K Distance
Organization: Commerce City Recreation Department
Date of Race: 12-06-2025
Description: DescriptionJoin us for our annual Run with the Buffalo ...
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Run with the Buffalo Fun Run: 2.5 Mile ...
Organization: Commerce City Recreation Department
Date of Race: 12-06-2025
Description: DescriptionJoin us for our annual Run with the Buffalo Ugly ...
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Run with the Buffalo Fun Run: 2.5 Mile ...
Organization: Commerce City Recreation Department
Date of Race: 12-06-2025
Description: DescriptionJoin us for our annual Run with the Buffalo Ugly ...
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Run with the Buffalo Fun Run: 5K Distance
Organization: Commerce City Recreation Department
Date of Race: 12-06-2025
Description: DescriptionJoin us for our annual Run with the Buffalo ...
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Run with the Buffalo Fun Run: 5K Distance
Organization: Commerce City Recreation Department
Date of Race: 12-06-2025
Description: DescriptionJoin us for our annual Run with the Buffalo ...
View Race Details View on Map
Complete list of running events in and near Boulder, CO: Marathons, 1-milers, 5Ks, half-marathons, 10Ks, obstacle courses, walking events & more.
More information about Boulder
About Boulder
Boulder (CO) is a city in Boulder County with an estimated population of 97,385.[4]
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Did you know?
The number of U.S. marathon finishers declined from 2014 to 2015 approximately 8 percent.
