Passo del Mortirolo, ITA

Southwest of the Gavia Pass lies the Passo del Mortirolo, also known as the Passo della Foppa. From Mazzo di Valtellina it is one of the most feared climbs in Italy and a fixture of the Giro d’Italia. No high pass, no grand panorama, instead a narrow forest road with gradients that push even the strongest climbers to their limit. A legend of road racing.

The Passo del Mortirolo at a glance

The classic ascent from Mazzo di Valtellina is 12.2 kilometres long and gathers around 1,360 metres of climbing, 11.1 percent on average. At its steepest it reaches up to eighteen percent. The summit sits at 1,852 metres. What makes the Mortirolo so hard is not the length and not the altitude, but the relentless steepness that barely lets up for a single hairpin. The name goes back to the dead and the battles of the First World War.

The climb from Mazzo

The road pitches up within the first few metres out of Mazzo. From around kilometre three the brutal middle section begins, the one that built the Mortirolo’s reputation. For about five kilometres the road holds twelve to fifteen percent, with short ramps up to eighteen. There is no recovery here, no flat hairpin, just forest, silence and the next gradient.

The dense woods take away the view and deepen the sense of isolation. Only in the final third, above the treeline, does the gradient ease a little and open things up. If you still have matches to burn up here, you paced it too well down below. You do not ride the Mortirolo, you survive it.

History and racing

Originally the Mortirolo was a steep trade route. Since 1990 the ascent from Mazzo has been part of the Giro d’Italia roughly every two years, where it is regularly declared the queen stage. One stage in 1994 made the pass immortal. On 5 June the Giro sent the field over the Stelvio, the Mortirolo and the Santa Cristina to Aprica. On the Mortirolo, Marco Pantani attacked, distanced the all-powerful Miguel Indurain and rode one of the most famous solo wins in cycling history.

Five kilometres below the summit a monument to Pantani has stood since 2006, the Memorial Pantani. On Giro stages a special prize is awarded to the first rider over the Mortirolo, the Cima Pantani. More than one climber has called the Mortirolo the hardest ascent in professional cycling, and anyone who has been to the top is slow to disagree.

Practical tips

A low gear is not a luxury on the Mortirolo, it is a requirement. At a constant ten percent and above, every spare sprocket counts. If you can, run a compact crankset with a big cassette, anything else turns the steep ramps into torture.

The road is narrow and runs almost the whole way through forest, which keeps the heat out but also takes away any cooling airflow. There is little traffic, which makes the climb pleasantly lonely despite all its harshness. The season runs roughly from May to October. There is food down in Mazzo, but almost nothing on the mountain itself, so stock up beforehand.

How does the Mortirolo stack up?

The Mortirolo is the pain pole among the great Italian climbs. The Passo di Gavia one valley over you ride for the scenery and the altitude, the Mortirolo you ride for the pure gradient. In the same category of merciless walls sits the Monte Zoncolan, the other Giro nightmare. Gavia, Zoncolan, Mortirolo: three different ways to suffer, and the Mortirolo is the most direct.

For us the Mortirolo is one of those climbs every fan of steep ramps has to ride once. If you want it on your wall, you will find it on our 100 Climbs posters, with the Top 50 edition also available in a more compact format.

How steep is the Passo del Mortirolo?

The ascent from Mazzo di Valtellina climbs at 11.1 percent on average over 12.2 kilometres, with ramps of up to eighteen percent. The brutal middle section holds twelve to fifteen percent over several kilometres with no real recovery.

Why is the Mortirolo so famous?

The Mortirolo is considered one of the hardest climbs in professional cycling. It became famous through the 1994 Giro stage, when Marco Pantani attacked here and took a legendary solo win. Five kilometres below the summit the Memorial Pantani remembers him.

What gearing do you need on the Mortirolo?

As low as possible. At a constant ten percent and above, with ramps up to eighteen percent, a compact crankset with a big cassette is strongly recommended. Run too big a gear and you will barely keep the pedals turning on the steep sections.