- Ascent
- 995 hm
- Distance Ascent
- 12.8 km
- max. gradient
- 13.5 %
- ø gradient
- 7.8 %
The Col de Sarenne from Mizoën is an HC climb of 12.8 km with 995 m of elevation gain at an average of 7.8 %, peaking at 13.5 %. The road climbs out of the Romanche valley via Clavans to 1,999 m. On the far side it runs down via Alpe d'Huez to Le Bourg-d'Oisans.
Climb Goals: Pure Data Edition DIN A1 poster
Bucket-List Print: Col de Sarenne
The Col de Sarenne is the back door to Alpe d’Huez. From Mizoën in the Romanche valley it is 12.8 kilometres and 995 metres of climbing up to 1,999 metres. At 7.8 % on average it is one of the steeper climbs in our list. On the other side the road runs via Alpe d’Huez down to Le Bourg-d’Oisans.
The Col de Sarenne at a glance
The key figures from Mizoën: category HC, 12.8 km, 995 m of climbing, 7.8 % on average and 13.5 % at its steepest. The road leaves the Romanche valley, climbs via Clavans and reaches the pass at 1,999 m. From there it crosses over to Alpe d’Huez and on down to Le Bourg-d’Oisans. In our list the Sarenne belongs to the Western Alps region.
The climb from Mizoën
We do not have a reliable kilometre profile for the Col de Sarenne, so this section only covers what the key figures can safely tell. 995 metres of climbing over 12.8 kilometres means the road gains almost 78 metres per kilometre on average. That is a value that means work over the full length, even if individual stretches may be easier.
The 13.5 % in the fact box is the steepest point, not the normal state: the gap between peak and average is a moderate six percentage points or so. For comparison, Alpe d’Huez pairs a 14.8 % peak with a 7.9 % average. Plan for a climb that costs energy all the way up rather than one with a single hard wall.
How it compares to our 100 climbs
On the average the Sarenne is well up the list: only 23 climbs are steeper on average, eight of the 30 in the Western Alps. On length and elevation gain it sits towards the back, 70 climbs are longer and 73 have more climbing. The obvious comparison is Alpe d’Huez on the other side: 13.8 km and 1,090 m of climbing at 7.9 %, almost the same gradient over slightly more distance. Put together, the two make a loop through the Oisans.
Practical tips
With 13.5 % at the steepest point, a compact chainset with a large sprocket makes sense. At almost 2,000 m it is noticeably colder than down in the Romanche valley, so bring a jacket for the descent. Carry on over the pass and you reach Alpe d’Huez, from where you roll down to Le Bourg-d’Oisans. The way back to Mizoën runs up the Romanche valley.
