While the summit sign reads 2,770 meters, the official summit of the Col de l’Iseran on the maps until recently read 2,764 meters.
At any rate, either makes it the highest paved pass in Europe, although the artificial loop around the Bonette is claimed as such by the French, or at least those in the Ubaye valley.
However, the official pass height of the Bonette is 2,715 meters, so the Iseran, the Stelvio (2,758) and the Agnel (2,744) are higher ‘by nature’…
The Iseran is part of the Route des Grandes Alpes (in French). It connects the valleys of the Isère (Tarentaise) and Arc River (Maurienne) between Val-d’Isère in the north and Bonneval-sur-Arc in the south.
The north side of the pass officially starts at Val-d’Isère, or further down from Bourg-Saint-Maurice. The climb from the south officially starts at Lanslebourg-Mont Cenis, but you could also consider Modane as the starting point.
Post WWII the Iseran was included in the Tour de France 5 times between 1947 and 2007 – in 1996 it was also scheduled, but that stage was rescheduled due to bad weather (snow on both the Iseran and the Galibier).
In 2019, the southern ascend was again included in a stage (19), which was scheduled to finish in Tignes, but that stage eventually got neutralized at the Iseran summit, because of bad weather and a landslide.
Bourg-Saint-Maurice
Starting from Bourg-Saint-Maurice, the climb to the summit of Col de l’Iseran is 47 (!) kilometers and over this distance, the road ascends over 2,000 meters – an almost modest average grade of 4.2%.
While those grades seem rather friendly, the sheer length of the climb makes it a hard one.
Plus, not considering the 17 kilometer ‘near flat’ sections at the bottom and through the tunnels past the lake of Tignes, the average over the remaining 30 kilometers is close to 6%.
The views higher up, past Val-d’Isere in the hair pins, are fantastic, as is the panorama at the summit.
There’s also a ‘refuge’, L’Èchoppe de l’Iseran.
If you go down to Modane, it’s worth taking the ‘Route Panoramique’ at Sollières-Sardières.
It’s more quiet and enjoyable, but it comes with some extra climbing to the Croix d’Aussois. That is easier from this end: 7.5 kilometers at 3.3% average, with 3.5 kilometers at/over 5%.
Report of my trip up this end in 2014 here and a video (starting in Val d’Isere) by the Col Collective here.
Lanslebourg
From the south, the official climb starts at Lanslebourg-Mont Cenis and is 32.9 kilometer long, with a 1,371 meter elevation gain, or an average grade of 4.2%.
The first 7 kilometers are up the Col de la Madeleine (not the Madeleine), with some 350 altimeters not the hardest bit, but it has 9% grades.
After that, there’s a 12 kilometer ‘flat’ section through the Bessans valley, where you will hopefully not have to face a headwind.
I descended this way towards Modane after my climb from Bourg-Saint-Maurice, with a little ‘detour’ up and down the Mont Cenis.
Thinking this was mainly downhill, I figured it would be relatively easy.
However, the section in the valley between Bonneval and la Madeleine, completely wore me out because of the strong headwind.
If you go the other way and would then also have to battle a headwind, you will face a very tough 12 kilometers – despite being used to riding headwinds (the famous ‘Dutch Mountains’), I know I would not be – and wasn’t – happy.
Without this flat section, the average of the climb increases to around 6%.
The hardest part, or the final, starts at Bonneval-sur-Arc: 13.4 km with 977 m of elevation (7.3%) with several stretches over 10%.
From this end, you could include the section between Modane and Lanslebourg as a ‘warm up’, adding some 23 kilometers with an additional 450 meters of elevation.
These come with some up- and downhill bits, but also for that part, the wind could be your greatest enemy, as I experienced first hand going the opposite direction…
Immediately upon leaving Modane, there’s a more scenic and quiet route, if you travel the D215 and continue the on the D83 near Aussois.
This is the ‘Route Panoramique’, as indicated when coming from the other direction, at Sollières-Sardières.
At the roundabout, turn left towards Le Bourget and Aussois.
It features an additional climb to the Croix d’Aussois: 8.6 kilometers at 5.4%, with a kilometer over 8%.
I cycled up this “intermediate” to continue to Plan du Lac, a fork off the Iseran in my 2021 Tour de France.
There’s a “freebie” col to be had from this end: just past the first hairpin section out of Lanslevillard, there’s a “Col de la Madeleine” (1,746m) marker.
Definitely not THE Col de la Madeleine, but still 😎
As mentioned above, there’s a ‘refuge’ for a snack and/or a souvenir at the summit of the Iseran.
Report on my 2021 Tour de France ascend, starting just outside of Sollières, here.
Tigne – Val Claret
If you’re in the mood, you can get to Tigne from either end.
From the south, you can keep right towards ‘Tignes > Les Brévières’ or keep right a bit further on, at le Chevril, towards ‘Tignes – Val Claret’.
The former is a bit longer at 9.5 kilometers, against 8 kilometers for the latter, but the altitude gain is the same, some 560 meters.
From the north, you will (obviously) have to descend from the summit of the Iseran towards and past Val d’Isère.
The above mentioned second alternative would then be the most logical route to take, starting just past the tunnel along Lac du Chevril.
The latter is what I did during stage 7 of my Tour de France 2021.
