The climb · France
About Port de Larrau
Port de Larrau rises with quiet menace from the start. The road immediately tilts upward, demanding respect and concentration as you leave the village behind. It’s a climb that feels both wild and remote.
The forested slopes hide the road’s every twist, so you can’t anticipate what’s coming next. Each ramp tests your pacing, and the effort accumulates almost without notice until you’re fully engaged.
At the summit, the mountains open up and the effort feels richly earned. This is a climb for riders who enjoy being pushed and value a route that rewards patience and courage.
01 / The ascent
Elevation profile
02 / The crux
Where it gets difficult
Choose a distance to find the steepest continuous section of the climb.
Steepest 500 m average
16.2%
Where to find it
4.10–4.60 km from start
- Net height gained
- 81 m
- Section length
- 500 m
03 / The numbers
Climb statistics
- Distance
- 14.77 km
- Elevation gain
- 1,180 m
- Average gradient
- 7.8%
- Climb category
- HC
- Start elevation
- 409 m
- Summit elevation
- 1,570 m
04 / Your effort
How long would it take?
Enter the power you could hold for the whole climb. We calculate a moving time from the elevation profile and the forces you ride against.
Use your intended climbing effort, rather than FTP unless you can hold it for the predicted duration.
Bike + kit includes clothing, bottles and luggage.
Advanced settings
Defaults represent a road-bike scenario. Adjust these settings to match your tyres, drivetrain and riding position.
Modelled moving time
1 h 21 min
- Power throughout
- 225 W
- Average speed
- 10.9 km/h
Based on the 14.77 km elevation profile. Assumes steady power, with no stops, braking or drafting. Rounded to the nearest minute.
The science behind the calculation
For each part of the stored profile, we solve the steady-state cycling power equation for speed, then add distance ÷ speed across the climb. Gravity uses rider + equipment weight; available power is W/kg × rider weight. This uses the profile’s distance and elevation together, without mixing in another route’s metrics.
Power × efficiency = gravity + rolling resistance + air resistance + bearing losses
The resistance equations are adapted from Martin et al. (1998), Validation of a Mathematical Model for Road Cycling Power. Air density changes with profile altitude using NASA’s standard-atmosphere model. This calculator’s adaptation has not been independently validated.
It predicts travel at the power you enter, including on descents. It does not model acceleration, cornering, braking, traffic, wind, changing weather or fatigue. At altitude, choose power you can sustain there: thinner air reduces drag, but this model does not predict its effect on your ability to produce power. Profile quality and assumed equipment settings also affect the result.
05 / On the ground
Route map
Route overview
Port de Larrau
Larrau, Nouvelle-Aquitaine, France
- Route length
- 14.77 km
- Total ascent
- 1,180 m
- Average gradient
- 7.8%
06 / Take it home
The climb, as artwork
Turn the route into a personalised topographic print. Choose your colours and composition, then download your artwork.
07 / Keep exploring
Nearby climbs
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Ibardin
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Puerto de Lizárraga
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Etxarri-Aranatz, Navarre, Spain
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Hourquette d' Ancizan
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Campan, Occitanie, France
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Lac de Cap-de-Long
13.4 km · 7.6% · 1039 m gain
Aragnouet, Midi-Pyrénées, France
97.4 km away · Explore climb →