One of Europe's hardest bike climbs is Passo del Mortirolo, a must ride.
The bike route up from Mazzo is classic way up and most well known. Utilized in various Giro d'Italia's this route has an average grade of 10.5%, with ramps up to 18%. The heart of the climb is 4 km section with an average grade of 14%.
Nuts and Bolts
| Departure Point | Mazzo in Valtelina |
| Elevation at departure | 551 meter |
| Highest elevation | 1851 meters |
| Length | 12.4 km |
| Elevation gain | 1300 meters |
| Average grade | 10.5% |
| Max grade | 18% |
| Average Ride Times | |
| Excursionist | 2 hours, 10 minutes |
| Cycle Tourist | 1 hour, 37 minutes |
| Semi Pro Racer | 1 hour 11 minutes |
| Professional Cyclist | 55 minutes, 40 sec |
