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Col de l'Iseran - Bourg Saint Maurice     open your myclimbbybike to add this climb

48 km  2770 m  (1955 m)  4.1 %


The Iseran is an incredibly long climb. From Bourg-St.-Maurice, it takes no less than 48 kilometers. Luckily the percentages are not too high and there are even some long descents to recuperate.

The Col de L'Iseran is one of the biggest climbs in France and from the Tour de France. Well deserved, although you wouldn't suspect that after the first part, up to the reservoir. You have to go through here to get to the real climb, which is magnificent. It's definitely a climb that has to be on everyone's bucket list.

From Bourg-St.-Maurice take the D902 to Sainte-Foy-Tarentaise. Soon you drive along the river Isère which will follow you almost to the top. Only after Sainte-Foy-Tarentaise follow some heavier stretches and flirt the climb with " yellow " (+ 7%). After 15 kilometers you'll reach La Thuile, after which the climb becomes a bit calmer again on annoyingly long straights. After passing the first exit towards Tignes (D87B) six kilometres further, the climb becomes more difficult again until you see the imposing dam of the reservoir on your right. What follows are 9 almost flat, sometimes even descending, kilometers to Val d'Isère. Pay attention and be sure to take some light with you on your bike, because here are only dark, narrow and therefore not very safe tunnels.

From the beautifully situated ski village of Val d'Isère the climb begins, after 33 kilometers really. What follows to the top belongs to the more beautiful climbing. Only now you see the actual Iséran. After the Pont-Saint-Charles it gets a lot steeper again. You are now at over 2,000 meters altitude and that crawls in the legs. In a little while you get a view on Val d'Isère with behind it, the Lac de Chevrvil. A few hairpin bends offer a welcome break. Between boulders, snow or remnants of snow, the climb back to the end becomes a bit easier. But after a few hours of climbing it is well deserved. Eventually you'll get to see the famous chapel at the top as well as a souvenir shop where you can refill things. In front of you is the snowy summit of the Grande-Sassière, almost 4,000 meters high.

The best part might follow, at least, if you drive on to Bonneval. If not, take the trouble to continue for a kilometre. After all, what follows is one of the most beautiful mountain ranges in the Alps.

The Col de l'Iseran is situated in Rhone-Alpes. This climb belongs to the Alps. The Col de l'Iseran via Bourg Saint Maurice is ranked number 138 of the Alps. If you want to climb the Col de l'Iseran, you can find more information on how to train to climb the Col de l'Iseran here.

Since 2005, the Col de l'Iseran will be/was climbed in the following big tour stages:
Tour de France 2007 :  Val-d'Isère > Briançon on 17/07/2007
Tour de France 2007 :  Le Grand Bornand-Tigne on 15/07/2007

Images of the Col de l'Iseran


Climbbybike difficulty score (152.8)
Ranking Alps
Ranking France

Col de l'Iseran via Bourg Saint Maurice popularity rank : 163

The Col de l'Iseran has been climbed by 40 climbbybikers. It is ranked No. 163 as the most climbed climb in the world.
Discover all the most difficult climbs in France and the most popular climbs in France.

Col de l'Iseran via Bourg Saint Maurice: 18 reviews

chris patient

I climbed the Col de l''Iseran from Bourg St Maurice and I did not enjoy the climb at all until I reached Val d''Isere from where it is a spectacular and very enjoyable road to climb by bike. I found the road from Bourg boring and busy and badly surfaced. Furthermore there are some dangerous tunnels inside which my strava bagging companions lost their signals to their dismay.

From Val, however it is a classic mountain pass road and well worth the effort particularly as it is so high.

David Hyland

We started the Climb from Bourg St Maurice. The climb to Val d''Isere is a fairly steady, not very steep but blighted by constant summer traffic. Reaching Val d''Isere at 1900m, you realise you still have a long way to go, still is bigger than the average climb!

After Val d''Isere, the ride changes, the road narrows considerably and traffic is less intrusive. On crossing a stone bridge the climb becomes much tougher with a classic hairpin road. The views looking down on Val d''Isere are truly impressive.

With 3km to go, the climb gets steeper making the final approach to Col d''Iseran a real challenge. We reached the top to see a fantastic vista on the far side of the col.... and a cafe too!

It''s not the toughest climb (Col de Madeleine is much tougher) but above Val d''Isere its beautiful with marvellous views down the valley.

john lees

Cycled to Switzerland from England in 1961, we did all the highest passes we could find, we just had to do the Iseran,via Torino then the Mont Cenis with overnight at Lansleborg . Next day it was the Iseran, amazing and good from that direction, we did not see any other cyclists. We did not think about altitude,still remember all of it. It was in late August but it was closed two days before due to snow.John Lees

Dave Eastburn

I rode the Iseran in September of this year to celebrate my 70th birthday. I last rode the Iseran when I was 30. The climb to Val d''Isere is the steeper part of the ride, but the climb beyond Val, which my bike computer told me averaged 5.5% is the hardest because of the altitude. I found myself using the 34-28 near the top. The one difference I noticed this time, due most likely to the conservatism of age, was the fear factor. After the turn above Le Fornet the road becomes very exposed, with steep drop-offs, and no protection. The frequent motorcycles are a noisy distraction, but you get used to them. I found the scenery quite intimidating as the mountains tower above the road, and often the nearest thing to focus on, besides the road ahead, is the town of Val d''Isere way below in the valley. Then you turn a bend, near the observation post, and you''re into the upper valley, all rock and scree. The last 200 yards makes you earn the summit at 8-10%. The altitude can drain your will, too, if you let it. One other thing I noticed: the glacier up at the top of the Iseran, Le Pissaillas, has virtually disappeared since I last rode my bike here. Back then, there were skiers cavorting on it. Now, it''s just a pile of scree.

david price

A must-do if you like ''em long. The gradient is managable on 34/25 but nonetheless, you will need patience and focus to keep your rhythm for the length of this monster. You''ll be full of anticipation climbing to Val d''Isere, knowing you''ll be only half way. Leaving the town, the landscape becomes more intimidating - look up at the beast you''re about to tackle and you''ll feel like a speck in the universe! As you gain height you may start to feel the altitude - keep breaths shallow. Look back down at Val and it looks like match-boxes on the valley floor. Keep tapping away and - hey presto! - you''re there. Make sure you''ve got the kit - cold at the top!

Steve Feldwick

Ive just returned from the Aps where I was watching Le Tour, but wanted to tick off a famous Col whilst I was in the vicinity. I started out the climb from a little village called La Thuile Savoie down the valley near Bourg St Maurice and have to say the consistently steepest gradients appeared to be on the climb up to Tignes, with the GPS showing 8 and 9% stretches fairly regularly. Once through the tunnels approaching Val dIsere (take lights!) there is a slight downhill stretch before passing through Val, then on the gradual grind up to the dramatic head of the valley where the road doubles back and up on its inexorable climb up into the clouds. The climb itself from this point isnt too steep, with a reasonably consistent gradient of between 6 and 8%. But beware the altitude, youre starting at 1850m at Val, but climbing up to nearly 2800m. Also, on the day I rode the weather dramatically changed near the summit with strong headwinds, thunder, lightning and sleet. Consequently I had to stop my descent and re-climb the top 2k to take shelter, very cold and wet. Thankfully there is a good (albeit pricey!)café at the summit. Its a dramatic Col with the wonderful payback of amazing views (and speed) on the descent!

jeremy north

It was in 2003. I was in Val dIsere to see the 4x4 show. Having been a fan of the tour de france for about 20 years, I took my bike, as it would be an opportunity to have a go at an Alp. Little did I know at the time of its significance, in that it is one of the less often cols included in the Tour. I hadnt ridden much for several years so wasnt ideally prepared for this monster. It was of course the hardest thing Ive ever done. 17 kilometres uphill without respite and on my old bike with a low gear of 42/24! The length and gradient werent the only challenge. There is the sneaky problem of altitude! For someone who has never been more than a few hundred feet above sea level apart from the extremely rare hike to three or four thousand feet, this was not something Id ever considered to be an issue. I was wondering why I was so short of breath. I had to stop a few times to have a breather for a moment or two but was determined to reach the top. At each bend, I was expecting to see the summit only to be faced with another stretch of tarmac leading to another horizon. The kilometre posts by the roadside were a frequent reminder of the struggle to come. It started at 17km but they seemed to get further and further apart as I huffed and puffed my way up the ascent. There were more and more pockets of snow embedded into the undulations, and this was the height of summer. I stopped to take a picture of a Marmot which I surprised (though it surprised me more!). Eventually the top of the Col. What a feeling of satisfaction, nay, triumph! Being alone all I could do was to take a photo of my steed, my 531c tubed Raleigh,along with my 2L water bottle, leaning against the famous sign. The descent was a lot quicker. However I was overtaken several times by guys in the proper attire who had bags more confidence than me on those hairpin bends. It was cold too rushing down. It was only much later that I realised the nature of this col in respect of its altitude etc. The Galibier looks like more of a beast but Ive conquered the biggest of them all, albeit at a shameful pace. This year, the Tour went over it again. Fair play to them, they rode up it at ease then the Telegraphe and the Galibier! All in a days work. Ill not give up the day-job! Yet

david staveley

A group of us cycled over the beautiful Col de lIseran in August 1959 - but got trapped by a snowstorm in the afternoon at the top & had to stay in the rest house there. The early morning descent to the Arc valley on the south side was quite difficult on the icy roads. We followed that event with tackling the Galibier!

Eleni Liakou

I want to pass col de lIseran and col du Galibier by car, on 26/05/2007.Please, tell me if this is possible.

Harm Selten

This is one of the most beautiful cols in the Alps. Its a climb over more then 40 Km. We went up with 20 kg luggage and it was good to do. We slept in Val disere in and very well organised camping site. The last 15 km of the climb arent diffucult but because of the height even very hard

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