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Col de l'Iseran from Bonneval-sur-Arc

Col de l'Iseran from Bonneval-sur-Arc: 13.2 km at 7.4% average and 979 m of climbing, up to 2,764 m.

Savoie

Opening Fermé l'hiver. La route du col est déneigée au printemps et rouvre en général entre fin mai et fin juin selon l'enneigement — vérifier l'état de la route avant de partir.

Distance
13.2 km
Elevation gain
979 m
Elevation loss
13 m
Average gradient
7.4 %
Start altitude
1,791 m
Road
Departmental road
Surface
Paved throughout
Steepest 500 m
12.0 %
Hardest 2 km
9.9 %
Hardest kilometre
km 12 · 10.1%
Above 8%
6.0 km (46% of the climb)
Difficulty index
8.8 Hard

FIETS index: Δaltitude² / (10 × distance) + max(0, summit altitude − 1,000) / 1,000, lengths in metres. How this index works (article in French)

See your own times on this climb

How long does it take?

Estimated climbing time, by level
Level Estimated time Average speed
2.0 W/kg — 140 W 1h39 7.9 km/h
3.0 W/kg — 210 W 1h08 11.7 km/h
4.0 W/kg — 280 W 52 min 15.2 km/h

Estimated for a 70 kg rider on a 9 kg bike, in still air, at a steady effort and without stopping. Wind, a stop at the fountain or a wheel to sit on move these figures by several minutes.

The route

246810122 km© IGN – PLAN IGN v2 · © les contributeurs d’OpenStreetMap
246810121 km© IGN – PLAN IGN v2 · © les contributeurs d’OpenStreetMap

Climb profile

1,8002,0002,2002,4002,600024681012mkm

Kilometre by kilometre

Gradient and altitude, kilometre by kilometre
Km Gradient Altitude at the top of the km
1 8.7 % 1,878 m
2 8.4 % 1,962 m
3 8.3 % 2,045 m
4 7.8 % 2,123 m
5 1.6 % 2,139 m
6 8.6 % 2,225 m
7 6.9 % 2,294 m
8 9.2 % 2,386 m
9 9.2 % 2,478 m
10 3.5 % 2,513 m
11 6.2 % 2,575 m
12 10.1 % 2,676 m
13 7.7 % 2,752 m
14 (partial) 2.9 % 2,757 m

The other climbs of this col

Frequently asked questions

How long is the climb to Col de l'Iseran?

The hardest climb of Col de l'Iseran, from Bonneval-sur-Arc, is 13.2 km long for 979 m of ascent, i.e. 7.4% average.

What is the steepest part of Col de l'Iseran?

The steepest 500 m sits at 12.0%, and the hardest kilometre is the 12th, at 10.1%.

How long does it take to climb Col de l'Iseran from Bonneval-sur-Arc?

Col de l'Iseran from Bonneval-sur-Arc takes about 1h08 at 3.0 W/kg, i.e. 11.7 km/h on average. The page gives three levels and their assumptions.

Is Col de l'Iseran open all year round?

Fermé l'hiver. La route du col est déneigée au printemps et rouvre en général entre fin mai et fin juin selon l'enneigement — vérifier l'état de la route avant de partir.

Col de l'Iseran: add this col to your collection

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