Ashdown Forest: Cycling Climb

The climb · United Kingdom

About Ashdown Forest

Collections

Simon Warren’s Another 100 Greatest Cycling Climbs

Ashdown Forest unfolds over a longer distance than most nearby climbs. From south-west of Groombridge, this approach heads towards the forest's higher ground, taking in about 7.6 kilometres of rolling road. The name can suggest a continuous ascent, but the route includes descents: height gained early is partly given back before the more sustained climb begins.

That broken opening gives the ride its particular rhythm. The pedals turn with less resistance on the falling road, then the effort gathers again as the latter part rises towards the finish. An overall average cannot convey those changes especially well; the experience is closer to travelling through the folds of the landscape than tackling one isolated hillside. By the final section, the road has settled into a more persistent ascent and the earlier interruptions are behind you. Its appeal lies in the length and changing movement of the approach.

01 / The ascent

Elevation profile

Start 43 m · Summit 221 m

Gradient by distance7.63 km / 244 m gain

0 km1.5 km3.1 km4.6 km6.1 km7.6 km

02 / The crux

Where it gets difficult

Choose a distance to find the steepest continuous section of the climb.

Steepest 500 m average

7.9%

Where to find it

0.50–1.00 km from start

Net height gained: 40 m
Section length: 500 m

The whole climb7.63 km

0 kmFinish

03 / The numbers

Climb statistics

Distance: 7.63 km
Elevation gain: 244 m
Average gradient: 2.3%
Climb category: Uncategorized
Start elevation: 43 m
Summit elevation: 221 m

Current weather

At the climb start

Loading weather…

Weather data: MET Norway

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.

Sustained power

W/kg

Use your intended climbing effort, rather than FTP unless you can hold it for the predicted duration.

Rider weight (kg)

Bike + kit weight (kg)

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.

Effective drag area (CdA) (m²)

Rolling resistance (Crr)

Drivetrain efficiency (%)

Modelled moving time

21 min

Power throughout: 225 W
Average speed: 21.6 km/h

Based on the 7.63 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