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Each year Alpe D’Huez hosts the finish of the famous sportive ‘La Marmotte’, one of the most popular and difficult amateur cycling events in Europe.  The race starts in Bourg D’Oisans, and then tackles the Col du Glandon, Col du Telegraphe, and then the Col du Galibier, before the final ascent up Alpe D’Huez.  By the time you get to the top you have completed more than 5000m of vertical climbing!

The Legendary Alpe D'Huez

Cycling Alpe D’Huez - Cycling the Legend

The legendary climb....all road cyclists have probably thought about cycling Alpe D’Huez one day.  With 21 bends over 13km and an average gradient of 8%, it’s not the longest or steepest climb in our part of the French Alps, but it is relentless. Our cycling accommodation is five minutes ride from Alpe D’Huez, in Bourg D’Oisans. If you have ridden the Alpe already you can work out your power using the calculator at the bottom of the page. If you haven’t had the chance to ride it yet and would like to give it your best shot then check out our Training for Alpe D’Huez page. The road is testament to its cycling heritage with the names of pro cyclists and flags spraypainted all the way up.  Visit after the tour has been up or after the yearly Dutch charity event Alpe D’Huzes if you want to see it in all its glory.

Cycling Alpe D’Huez

Alpe D’Huez is a cycling legend - and it didn’t get to be that way by being an easy climb!  If you are not experienced in riding in the mountains then one of the most important things to remember is that it goes on for a long way!  You’d be amazed at the number of cyclists who over-extend themselves for the first 5 - 10 minutes, go into the red and then struggle from then on.  Of course it’s easy to get taken in by the atmosphere - not only are you climbing the most famous mountain of the Tour de France, there will also likely be a lot of other cyclists doing the same (up to 1000 people a day at the height of the season) so you need to resist being drawn into a race.  Another factor is that the first 6 bends up to La Garde - around 10 to 15 minutes of climbing for most of us - are the steepest part, averaging around 11%.  

Once you have reached La Garde, the road gradient briefly drops.  You wont get long, so make the most of it! After a hundred metres or so it kicks back up again, but at more like 8 - 9%, rather than the 11% you have been doing.  This doesn’t sound like much of a change but considering that all you are doing is fighting is gravity, it makes a big difference.  

The next portion to Huez is the longest section, and it’s best to be riding hard, but keeping something in reserve.  A hard but not full effort tempo here can make the difference between riding to the end and achieving a good time and blowing up and wishing it was all over during the last part of the climb.  As you enter into Huez then come out the other side (a good few minutes later), you are into the last 1/3rd.

For this section, there is sometimes a slight headwind as you near the last 3 - 4 bends (just when you don’t need it!).  This is where keeping a little in reserve will have been worthwhile - if you’ve got it right you’ll probably pass some riders here as a lot of people run out of steam at this section.  As you turn the last bend, and catch sight of the hotels and shops ahead of you up the road, the road gradient deceivingly lessens.  Don’t quite put your final effort in now though as it kicks up again before the end and even though there is only 500 metres left it will seem like a long way!   You probably won’t have anything left for a sprint under the arrival banner but well done if you do!  Make sure you stop the clock and then reward yourself with a drink at the cafe next to the finish - congratulations!

Switchback on Alpe D'Huez

During the summer months the local tourism office organises timed ascents of the Alpe.  It’s a mass start event from Bourg D’Oisans - you ride as a group to the base of the mountain then your timing chip starts the clock.  For just 5 euros you get to put a number on your bike, ride Alpe D’Huez, and get a certificate on completion.  As most people want to see what their time is for getting up the mountain, this is a good way to make it official, and get a souvenir too.  Plus there’s food at the end!

Alpe D'Huez profile

Alpe D’Huez Profile

The profile of Alpe D’Huez shows its relatively constant slope, with only the hairpins giving a few seconds of relief where you can take a quick gulp from your water bottle.  The stretch of flat road east of the base of the Alpe is good for giving you a chance to do an out and back warm up before you hit the 11% slope at the bottom and start your stopwatch!

The relative steepness and consistency of the climb, and the effect of the switchbacks (so wind is rarely a factor), means that it is possible to fairly accurately calculate your effective power based on times achieved when climbing Alpe D’Huez.  

The first course (12.35km) finishes at the tourist information office and climbs 1023m , and the second takes you all the way to the top (the official tour finishing point, 13.65km long, 1072m of ascent).  

Most people stop at the first point but just in case you went all the way you can work out your power too!  For the engineers (that’s me) the following calculations assume an average CdA of 0.4 (typical value for a rider with hands on the bar tops) and rolling resistance coefficient of 0.005, although the effects of these are very small compared to that of gravity.

There is no provision for headwind, but as mentioned previously, this should not have much of an effect on the result.

This calculator will work for any climb where the effects of wind are negligable.

Time in minutes (min)

Weight of bike and rider (kg)

Power (watts)

Distance of climb (km)

Total ascent of climb (m)

(12.35km short course, 13.65 for long)

(1023 short course, 1072 for long)

Determine Average Power Output based on your time up Alpe D’Huez