Colle delle Finestre, ITA

At kilometre 12, the tarmac ends. Just like that. Mid-climb, the road turns to gravel. 7 kilometres of sterrato to the summit. This is Colle delle Finestre. The pass that flips the Giro d’Italia upside down every single time.

The Route

From Susa (Piedmont) it’s 18.5 km with 1,693 metres of elevation gain. The first 12 kilometres are paved: smooth riding, a steady 7-8% gradient, through chestnut forest. Nothing remarkable. You might think this is just another Alpine pass.

Then comes the sign: “Strada non asfaltata.” Everything changes. The gravel is coarse, uneven, littered with loose rocks in places. The gradient stays at 8-9%, but on gravel that feels twice as steep. Grip becomes the issue. Standing up barely works, sitting down you lose traction. 25mm tyres are the bare minimum, 28mm better. Tubeless recommended.

The final 2 kilometres before the summit (2,178 m) are the most emotional. The forest falls away, alpine meadows take over, and the view opens across the entire Susa Valley. The gravel road winds upward in wide sweeping curves. At the top there’s a small monument. Silence. Wind. Dust on your shoes.

The descent towards Sestriere is paved. Relief.

History and Pro Cycling

The Finestre first appeared in the Giro d’Italia in 2005 and instantly became a legend. The gravel turns every stage into an adventure. In 2015, Alberto Contador destroyed the field on the sterrato. In 2018, Chris Froome launched his legendary 80 km solo over Finestre and Jafferau to win the Giro.

The organizers love the Finestre because it blows the peloton apart. No team tactics can save you on gravel. Only power, bike handling and willingness to take risks matter here.

Tips for Cyclists

Tyre choice is everything. 25mm clinchers with inner tubes work, but a puncture on the gravel is likely. Tubeless at 28mm is the safe bet. Bring a spare tube anyway.

Best time: July to September. The gravel road is snow-free only late in the season. Fill your bottles in Susa, there’s nothing until the summit. The descent to Sestriere is fast and paved. If you want to ride the Finestre as a loop: climb from Susa, descend to Sestriere, return via Col du Montgenèvre (France). 120 km, three countries, one unforgettable day.