From Casteldelfino (4,199 ft / 1,280 m) to the Colle dell’Agnello (9,003 ft / 2,744 m) it is 13.9 miles (22.4 km) at an average of 6.5% with 4,803 ft (1,464 m) of climbing, according to salite.ch and Wikipedia. CyclingCols and Climbfinder measure the climb from farther down, from Sampeyre: 19.6 miles (31.6 km) and about 5,870-5,900 ft (1,790-1,800 m) of climbing.
What the climb is like
The 6.5% average hides a climb with two very different faces:
- Casteldelfino to Chianale. The Varaita valley climbs at moderate grades with the odd kicker, through Pontechianale and along the shore of its reservoir. This is the part to save your strength on.
- Chianale to the top. Chianale is the last village. From here the road heads into the high mountains and the grade shoots up: according to CyclingCols, the hardest 3.1 miles (5 km) average 10.5%, with ramps of 15%. There are few bends, so you can see much of the road still ahead.
The top is a pass of rock and meadow at 9,003 ft (2,744 m), on the border with France. On the other side you descend into the Queyras valley.
Its history
It is the third-highest paved pass in the Alps, after the Iseran and the Stelvio, and the highest border crossing in the range, although it sees little traffic. It is one of many places proposed as Hannibal’s route toward Rome; a plaque commemorates it on the French side.
The Tour de France crossed it for the first time on July 20, 2008, and came back in 2011. The Giro d’Italia has climbed it four times; on the last occasion, in 2016, Michele Scarponi crested it first (CyclingCols).
When to go, water and traffic
It is a very high mountain pass: it usually opens in late spring and closes with the first fall snow. Check its status before you go. Fill your bottles in Chianale: there is nothing above it until the top. The weather changes fast; bring warm clothes.
What gearing to use
At 3 W/kg (watts per kilogram of body weight) and 159 lb (72 kg), you ride about 5.6 mph (9 km/h) on 10%; on a 34x32 that is about 67 rpm, and on a 34x34, 71 rpm. Given the altitude and the hard finish, fit a 34x32 or lower. Compare in the gear calculator.
Tips
- Ride the valley up to Chianale below your threshold.
- Above 8,200 ft (2,500 m) you feel the lack of oxygen: do not force it on the final ramps.
- Check that the pass is open before you set off.
Frequently asked questions
How long does it take to climb the Colle dell'Agnello from Casteldelfino?
A 159 lb (72 kg) rider on a 21 lb (9.5 kg) bike takes about 1 hr 42 min at 3 W/kg (216 W), 2 hr 01 min at 2.5 W/kg and 1 hr 19 min at 4 W/kg. Work out your own time with your weight and power in the calculator on this page.
How high is the Colle dell'Agnello?
9,003 ft (2,744 m). It is the third-highest paved pass in the Alps, after the Iseran and the Stelvio, and the highest border crossing in the range.
Where is the hardest part of the Agnello?
In the last few miles, above Chianale. CyclingCols gives 3.1 miles (5 km) in a row at 10.5% and ramps of 15%.