The col des Glières lies 15km (as the crow flies) to the east-north-east of Annecy, and connects the town of Thorens-Glières to Le Petit Bornand in the valley of the Borne. The summit is on a large flat area known as the Plateau des Glières, which became famous as the scene of fierce fighting by the French Resistance in 1944.
Climbing the col des Glières
There are two possible ways up. One is steep, the other is very steep. Coming from the west the road is paved all the way to the col, where there is a large parking space and a memorial to the Resistance. Coming from the east (the steeper side) the paved road stops at the start of the plateau, and the final 1.8km are on a gravel road at a gentle gradient. This is the direction that will be taken by the Tour de France in 2018.
From Le Petit Bornand (east to west)
This is the direction the Tour de France will climb it. The climb is relatively short but unusually steep for the Alps. The total distance to the col from the turn-off in the valley is 7.9km, but nearly all the climbing takes place over just 6km. The road is very narrow and thankfully has almost no traffic.
Once the climb starts you can expect to be at never less than 10% for the first 4.5km, and frequently at 12% or more. There is a short respite around the 4.5km mark before the road steepens again to 12% and even 13% for the final push to the plateau.
Arriving at the plateau the road abruptly levels off and the tarmac ends. The gravel road for the remaining 1.8km to the col is perfectly passable on a road bike. It rises gently at an average gradient around 2.5%.
From Thorens-Glières (west to east)
The distance to the col from Thorens-Glières is 14km, but the first 1km is flat and the next 4 km are at 3% so barely count. The real climb begins just after the small village of Nant Sec. From here there are 9km to the col at an average of 7%. The last 2 km however include a short descent and a much easier 5% for the remainder, so the bulk of the climb is at gradients between 9% and 10%.
It is a pleasant climb on a wide, well-surfaced road with multiple switchbacks for much of the way.
The col des Glières in the Tour de France
The col des Glières will make its first appearance in the Tour de France in 2018, when it will be the second of four tough climbs on Stage 10, from Annecy to Le Grand Bornand. This same route will be used by over 12,000 amateur cyclists on the Etape du Tour, July 8th 2018.
We will be following this route during each of our training camps in La Clusaz, as well as our dedicated Etape du Tour training camp on 1-8 July. Contact us if you wish to ride in this epic challenge: we may still have some bibs.