Mortirolo Pass

Mortirolo Pass is the steepest climb on the pro circuit, with a maximum gradient of 18.2% that surpasses the Dolomites’ Sella Ronda by 6% in peak incline. On the 12.4-kilometer ascent from Mazzo, average gradient hits 10.5%, requiring riders to produce over 6 watts per kilogram for 45 minutes—a 30% higher sustained power output than what Il Lombardia demands on its steepest ramps. Unofficial KOM times in 2025 hovered around 42 minutes, making it 8% faster than the record on the Zoncolan due to Mortirolo’s shorter length.