40 Mile Bike
NEW COURSE for 2025!
12pm start time
Rolling gravel roads, beautiful views of 14ers, a loop around Boulder Reservoir, and life-long memories with 1000+ two-wheeled buddies. This course is a tour of some Boulder County’s best riding, including non-technical gravel riding and scenic views of the Rocky Mountains. There is enough rolling terrain to make the course challenging, but no major climbs or trails on this course. The aid stations at Boulder Res and Butter Ranch will warm you up and keep you fueled before the last stretch back to Lyons.
For those that ride AND run, this is the course that is the bike portion of the Run/Bike Combo.