RMCC South Jeffco Climbing Blowout
Rocky Mountain Cycling Club's season-finale Challenge Series road ride through South Jefferson County — packed with elevation gain and the best climbing roads near Denver.
The vibe
Season finale suffering session
The Blowout is exactly what it sounds like: RMCC’s way of closing out the Challenge Series season with a proper send-off. South Jefferson County has some of the best climbing roads on the front range — quieter than the canyon roads north of Denver, with grades that reward the fitness you’ve been building all summer. September timing means the air is cooling down just as your legs are peaking.
This ride rounds out the 2026 Challenge Series, which runs Mt. Blue Sky in June, Guanella-Loveland-St. Mary’s in August, and finishes here in mid-September. Do all three and you’ve had a genuinely impressive climbing season. The Jeffco routes are well-suited for a final hard effort before the riding volume drops off for fall.
RMCC membership required. Route details will be posted closer to the date at rockymountaincyclingclub.com. South Jeffco roads can be narrow with limited shoulder — group size and riding discipline matter out here. Plan to be self-sufficient with food, water, and repair equipment.