Two of Italy’s toughest climbs – the Passo dello Stelvio and Monte Zoncolan – featured in part one of our guide to the world’s must-ride climbs and here’s another contender for the title.

There are three routes up the Passo di Mortirolo but the fearsome ascent from Mazzo di Valtellina is the only one to consider if you want maximum kudos thanks to an average gradient of 11 per cent (peaking at 18 per cent) over a leg-numbing 11.4km.

The Mortirolo has featured in the Giro d’Italia 10 times, including in 1994, when the first rider over the summit was a 24-year-old Marco Pantani and that day is marked with a memorial of il Pirata on the climb.

Vital statistics

Length: 11.4km
Average gradient: 11 per cent
Start elevation: 576m
End elevation: 1,834m