The climb · United Kingdom
About Countisbury Hill
Countisbury Hill rises east from Lynmouth on the A39, carrying the road above the coast into Exmoor. The stored ascent is roughly 3.2 kilometres long, with its strongest opening effort close to the town. The Bristol Channel lies beside the climb, giving the ride an outward-looking character even while the gradient keeps attention firmly on the road ahead.
As height accumulates, the relationship between coast and hillside becomes more apparent: Lynmouth falls behind and the higher country takes over. The slope changes along the way, asking for adjustments rather than one unbroken rhythm, and the closing section still has climbing to contribute. This is a coastal ascent with enough length to feel substantial, rather than a short escape from the waterfront. The combination of an immediate rise and the surrounding sea gives Countisbury a distinctive place among Exmoor's roads.
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
15.2%
Where to find it
0.10–0.60 km from start
- Net height gained
- 76 m
- Section length
- 500 m
03 / The numbers
Climb statistics
- Distance
- 3.23 km
- Elevation gain
- 290 m
- Average gradient
- 9.3%
- Climb category
- 3
- Start elevation
- 7 m
- Summit elevation
- 299 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
20 min
- Power throughout
- 225 W
- Average speed
- 9.9 km/h
Based on the 3.23 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
Countisbury Hill
Lynmouth, England, United Kingdom
- Route length
- 3.23 km
- Total ascent
- 290 m
- Average gradient
- 9.3%
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
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Black Mountain
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Symonds Yat
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Bwlch-y-Groes
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170.6 km away · Explore climb →
