La Marmotte Alpes: 8 Mistakes to Avoid (My Experience since 2008)

Thinking about tackling the La Marmotte Alps Cyclosportive?

Don’t make the same mistakes most riders make. Your legs — and your sanity — will thank you during the ride.

La Marmotte is one of the toughest amateur cycling events in Europe:
174 km with over 5,000 metres of climbing across some of the most famous Alpine passes.

The route includes:

  • Col du Glandon
  • Col du Télégraphe
  • Col du Galibier
  • the final climb of Alpe d’Huez

After riding the event and supporting clients since 2008, I’ve seen the same mistakes repeated again and again. Here are eight simple ones to avoid

.1. Starting Too Hard From Bourg d’Oisans

The start in Le Bourg‑d’Oisans is chaotic.

The peloton surges forward and it’s very tempting to follow.

Resist it.

The first 10–12 km to Allemond are the only real warm-up and one of the few flat sections of the entire route.

Control your effort here.

You still have:

  • the Col du Glandon
  • the Col du Télégraphe
  • the Col du Galibier
  • and the final ascent of Alpe d’Huez

Early restraint pays off later in the day.

2. Stopping at the Col du Glandon Feed Station

Avoid the feed station at the top of the Col du Glandon.

It’s absolute mayhem.

Instead:

  • carry enough food for the first part of the ride
  • stop lower down if needed
  • keep moving over the summit

The descent is neutralised, and for good reason.

It’s long, twisty and dangerous.

If you’re riding for time, remember:

You can stop and rest inside the neutralised descent without losing official time.

3. Climbing Alpe d’Huez Before the Event

Many riders arrive a few days early.

And yes — the famous Alpe d’Huez is on everyone’s bucket list.

But don’t make it your first ride.

Instead try:

Save your legs.

You’re here to ride the sportive first.

Fast times on Alpe d’Huez can wait until after the event.

4. Trying to Do Too Much Before the Event

It’s tempting to explore all the famous climbs in the Oisans before the event.

But that often backfires.

Ride lightly before the sportive.

Then once you’ve finished La Marmotte, spend a few days exploring properly.

Great quieter climbs include:

Accommodation is often cheaper after the event and the roads are quieter.

5. Dressing Wrong at the Start

Morning temperatures in Le Bourg‑d’Oisans can be surprisingly cold.

Before the sun rises above the mountains, riders can spend a long time waiting at the start line.

Bring layers.

Many riders wear an old jacket they can discard before the start.

Remember:

Weather in the valleys can be warm while the high passes are freezing.

On the Col du Glandon, Col du Galibier, and Col du Lautaret, conditions can be cold, windy and wet even in July.

6. Spending Too Long at Summits

Many riders stop too long at mountain tops.

But the moment you stop climbing, your body temperature drops quickly.

Instead:

  • take a quick photo
  • grab food if needed
  • descend carefully
  • regroup with friends at the bottom

It keeps your legs fresh for the next climb.

7. Forgetting the Lautaret Tunnels

Most accidents happen in the tunnels between Col du Lautaret and the bottom of Alpe d’Huez.

The tunnels are:

  • dark
  • damp
  • slippery
  • and sometimes windy

Good habits here:

  • turn on lights
  • remove sunglasses
  • stay alert
  • ride predictably

The downhill section and headwinds can also drain energy quickly before the final climb.

8. Staying on Alpe d’Huez

Many riders stay on Alpe d’Huez during the event. Basing yourself in Le Bourg‑d’Oisans or Allemond gives you more flexibility.

Why?

The route returns to Bourg-d’Oisans before the final climb.

If you’re completely spent after the Col du Lautaret descent or miss the cutoff, you can simply turn left and ride home.

If you’re staying up on Alpe d’Huez, you have no choice but to climb.

Finish the 21 bends of Alpe d’Huez, and you’ve earned the descent back to the valley — and a well-deserved cold beer.

Free La Marmotte Route Map

If you want a free downloadable La Marmotte route map, complete your details below and make sure to leave a comment on the video


    You can also download the GPX route and watch my flyover route video where I share more insights from 17 years of riding the event and supporting cyclists.

    Part of the La Marmotte Preparation Series

    This article is Part 1 of a 3-part La Marmotte guide.

    Coming next:

    Part 2: How to Pace La Marmotte Properly
    Part 3: The Best Training Rides Around Bourg d’Oisans