Boulderthon 5K
Boulder, CO, USA · September 26, 2027·
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Distance: 3.1mi
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Race Info
The Boulderthon Heart to Heart 5K is a 3.1 mile out-and-back on the paved roads of east Boulder. It starts at 18th and Pearl Street, runs east along Pearl Street, and returns to finish in downtown near the Pearl Street Mall. The course is mostly flat with a gradual rise on the way back, at about 5,300 feet of elevation.
Race weekend
Sunday, September 26
7:00 AMMarathon (26.2 mi)7:00 AMHalf Marathon (13.1 mi)7:45 AM5K (3.1 mi)
8:10 AM10K (6.2 mi)FAQ
When is the 2027 Boulderthon 5K?
The 2027 Boulderthon 5K will be held on Sunday September 26, 2027.
What will the weather be like for the 2027 Boulderthon 5K?
The forecast calls for a high of 84°F and a low of 59°F with a 0% chance of rain. Check our detailed hourly forecast above for the best 5K race plan.
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