Thwaites Brow: Cycling Climb

The climb

About Thwaites Brow

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Simon Warren’s Another 100 Greatest Cycling Climbs

Thwaites Brow climbs south from the outskirts of Keighley, with a cobbled section that gives the road a character quite separate from its gradient. The selected ascent is about 1.2 kilometres long and averages roughly ten per cent, so the slope would already make a substantial climb on a smoother road. Over the stones, the task becomes less regular: the contact between tyre and surface interrupts the neat rhythm that a sustained gradient might otherwise allow.

That change of texture keeps your attention close to the bike and the next few metres of road. The cobbles are a defining passage within the ascent, rather than a reason to overlook the climbing around them. Height accumulates quickly over the short route, and the southward climb leaves the lower town behind. Thwaites Brow is memorable for the combination of a serious bank and a surface that refuses to let the effort become entirely routine.

01 / The ascent

Elevation profile

Start 101 m · Summit 224 m

Gradient by distance1.22 km / 123 m gain

0 km0.2 km0.5 km0.7 km1 km1.2 km

02 / The numbers

Climb statistics

Distance: 1.22 km
Elevation gain: 123 m
Average gradient: 10.1%
Climb category: 4
Start elevation: 101 m
Summit elevation: 224 m

Current weather

At the climb start

Loading weather…

Weather data: MET Norway

03 / 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

8 min

Power throughout: 225 W
Average speed: 8.9 km/h

Based on the 1.22 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.

04 / On the ground