Marmotte Granfondo Alpes: Course, Elevation & Route Profile

Course & Elevation

The start is at first light from 06:30 in the middle of Bourg d'Oisans at 722 metres. After about ten flat kilometres the Col du Glandon begins, a long and irregular climb that steps up to 1,880 metres by kilometre 36.5: 6.2 kilometres at 7.6 percent, then 6.7 at 7.7, then a closing 2.5 at 7.1. Timing is frozen on the descent for safety – the organiser wants that technical section ridden slowly.

In the Maurienne valley, the lowest point of the loop at 457 metres, the main course begins: the Col du Télégraphe from kilometre 80 measures 12.7 kilometres at 6.7 percent, and after the Valloire aid station the Galibier follows from kilometre 101 over 13.8 kilometres at 7.4 percent. Together that is roughly 2,000 metres of climbing in 35 kilometres, topping out at 2,637 metres where snow walls still line the road in early summer. The long descent over the Col du Lautaret runs almost fifty kilometres back to Bourg d'Oisans, broken by one short steep ramp around kilometre 152. Because of several poorly lit tunnels on that stretch, the organiser makes individual lighting compulsory.

At kilometre 162.5 the last difficulty starts: 13.1 kilometres at 8.3 percent to Alpe d'Huez, with the first two of the 21 hairpins averaging 13 percent. After more than 160 kilometres and 4,000 metres of climbing, it is the hardest ascent of the day. The cut-offs stand at the Galibier at 15:30 and at the foot of the Alpe at 17:45; feed stations are at the Glandon (km 36), Valloire (km 98), the Galibier (km 115) and Bourg d'Oisans (km 162).

Pacing Strategy

The Marmotte is lost on the Glandon and decided on the Alpe. The first climb starts ten kilometres in with fresh legs, cool morning air and a dense field – the three conditions under which almost everyone rides too hard. Hold an intensity that feels clearly too easy after twenty minutes: three more major climbs and over 4,000 metres of ascent are still ahead.

The race-deciding section is the Télégraphe–Galibier block between kilometre 80 and 115. Two thousand metres of climbing in 35 kilometres with only the short dip at Valloire between them, at increasing altitude and in midday heat. Ride the Télégraphe well below threshold, eat properly at Valloire, and ration the Galibier so that its final three kilometres above 2,400 metres stay rideable. For slower riders the 15:30 cut-off at the top is the real opponent.

The classic trap is the long descent to the Lautaret and on to Bourg d'Oisans. Almost fifty kilometres downhill feel like recovery and are therefore ridden fast and without eating – yet this is the only place in the race where you can take on calories calmly, and the tunnels demand lights and attention rather than speed. Use the descent to refuel and you arrive at the Alpe with substance; race it and you are in the red by hairpin 19.

Training plan for Marmotte Granfondo Alpes: 12-week build

Expect seven to eleven hours in the saddle; the 17:45 cut-off at the foot of the Alpe sets the hard limit. The demand is four long climbs of between forty minutes and well over an hour, joined by long descents and one flat valley stretch – a pure climbing-endurance test in which more than half the ride is spent going uphill.

Training centres on long rides with a great deal of vertical. Five to eight hours with 2,500 to 4,000 metres of climbing is the core work, and at least one of those should contain two climbs of over an hour each – that is the Télégraphe-and-Galibier structure. Short hard hill intervals do not prepare you for this race; what is needed is the ability to climb steadily just under threshold for an hour at a time, four times in a day.

The race-deciding phase is the last climb. So rehearse climbing under fatigue deliberately: after five or six hours of a long ride, add a 45 to 70 minute ascent rather than putting the hardest ramp at the start. Check your gearing on those sessions too – thirteen percent in the first hairpins of the Alpe after 4,000 metres of climbing demands a far easier sprocket than feels right on your local hill.

On conditions: the start is in late June at dawn temperatures, the high point sits at 2,637 metres with snow walls beside the road, and the closing kilometres to the Alpe fall in afternoon heat for most riders. Train for both – heat tolerance for the late afternoon and cold protection for the descents – and plan a gilet and arm warmers in. The compulsory lighting for the tunnels on the Lautaret descent is not a formality: buy and test the light beforehand, and practise long descents while eating on the move.