Climbing The Box: The Numbers that Matter – Height, Length, Gradient & Power for the Surrey Alpe
Box Hill gets a huge amount of airplay, considering its not particularly long or steep, but the ‘fear factor’ is generally lower than that of its nearby cousin, Leith Hill.
The Box Hill climb finishes some 171 metres higher than when you started – that’s 20m ‘more climbing’ than for Leith (roundabout to just past post box). In fact there are 204 metres of total elevation gain.
Of course the ‘full climb’ height gain is spread out over a much longer distance than Leith – at 4.3km its over twice as long.
The avg gradient is 4%, max’ing out (Strava says) at 13.3% in the stretch as you climb out of the last bend to the NT car park.
Pro cyclists (primarily those taking part in the 2013 RideLondonSurrey Classic) dominate the leaderboards. For the ‘full segment’ it hovers around the 7m 39s mark. That’s a cool avg speed of 33.7kph.
Most people are probably going to take between 8-15 minutes to do the ‘full climb’, with the more memorable section (the zigs & zags) taking around two-thirds of that time.
Here are some numbers (see attachment table) based around the ‘zigzag’ segment (generally understood as 2.2km in length). We’ve used a distance of 2.5km and gradient of 5%, with a selection of rider/bike weights.
Note: does not allow for environmental factors, such as wind, or other resistance variances (such as drafting, rolling resistance, bike performance, etc).
Next time you climb The Box, its worth thinking about what output you may need to be delivering for a certain PB time: