The Boulderthon is a popular marathon event held annually in Boulder, Colorado, offering a marathon, half marathon, and 5K race options. The course takes runners through the scenic streets of Boulder, with breathtaking views of the Flatirons and the surrounding Rocky Mountains. Known for its challenging course, the race offers an opportunity to experience both the natural beauty and vibrant atmosphere of Boulder, a city famous for its outdoor lifestyle. The Boulderthon attracts a diverse range of participants, from elite athletes to casual runners, all united by their love of the outdoors and running. With strong community support, great organization, and a focus on wellness, the Boulderthon is a highly anticipated event in the region’s running calendar.
Races
Marathon
Half Marathon
10km
5km
Race Date:
28 September, 2025
The Boulder Marathon, organized by Stronger Faster Boulder Co, offers a 26.2-mile scenic route through Boulder, Colorado, on September 28, 2025. With 293 meters of elevation gain, this Boston Marathon-qualifying race challenges runners with rolling terrain and stunning mountain views.
Weather based on historical averages. Route data provided by Strava, based on last year's race.
FAQs
What is the Boulder Marathon?
How long is the Boulder Marathon?
Where does the Boulder Marathon take place?
What is the elevation gain of the Boulder Marathon?
How can I prepare for the Boulder Marathon?
How do I choose the right training plan for the Boulder Marathon?
The Boulder Marathon, organized by Stronger Faster Boulder Co, offers a 26.2-mile scenic route through Boulder, Colorado, on September 28, 2025. With 293 meters of elevation gain, this Boston Marathon-qualifying race challenges runners with rolling terrain and stunning mountain views.
The Boulder Marathon is 42km long.
The Boulder Marathon takes place in Boulder, Colorado, USA.
The Boulder Marathon elevation gain is 293 meters, which Runna classifies as a Rolling race.
The best way to train for the next race is to use a personalized training plan that takes into account your current running ability, schedule, and preferences.
This will help you steadily improve your running performance and get ready for the race without risking an injury.
Check out our training plans to find the best running program for your goals!
Which plan you choose will depend on your experience, schedule, objectives, and the date of the race.
Runna offers personalized training plans for every runner and every goal: Whether this is your first, 10th or 100th race, we'll help you get the most out of your training and smash your goals.
Check out our training plans to find the best running program for your goals!
What is the Boulder Marathon?
The Boulder Marathon, organized by Stronger Faster Boulder Co, offers a 26.2-mile scenic route through Boulder, Colorado, on September 28, 2025. With 293 meters of elevation gain, this Boston Marathon-qualifying race challenges runners with rolling terrain and stunning mountain views.
How long is the Boulder Marathon?
The Boulder Marathon is 42km long.
Where does the Boulder Marathon take place?
The Boulder Marathon takes place in Boulder, Colorado, USA.
What is the elevation gain of the Boulder Marathon?
The Boulder Marathon elevation gain is 293 meters, which Runna classifies as a Rolling race.
How can I prepare for the Boulder Marathon?
The best way to train for the next race is to use a personalized training plan that takes into account your current running ability, schedule, and preferences.
This will help you steadily improve your running performance and get ready for the race without risking an injury.
Check out our training plans to find the best running program for your goals!
How do I choose the right training plan for the Boulder Marathon?
Which plan you choose will depend on your experience, schedule, objectives, and the date of the race.
Runna offers personalized training plans for every runner and every goal: Whether this is your first, 10th or 100th race, we'll help you get the most out of your training and smash your goals.
Check out our training plans to find the best running program for your goals!
More
Sport:
Running
Tags:
Dog Friendly
This event listing is for informational purposes only. Runna is not affiliated with, endorsed by, or sponsored by Boulderthon: Boulder Marathon presented by PUMA or BOLDERBoulder. All event details are based on publicly available information and are provided solely to help users discover running events. Runna does not use any official logos, images, or proprietary content from this event or its organiser. Any trademarks or names mentioned are used descriptively to identify the event in a factual manner. For the most accurate and up to date information (including to register or purchase an entry to the event), please visit the Boulderthon: Boulder Marathon presented by PUMA website.
