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There are probably about twenty 1:4 road climbs in the Cotswolds, many of them on its northwestern scarp edge or in the deep-cut Frome valley south-east of Stroud. I have ridden most of them, successfully climbing nearly all of those I’ve attempted, at least when circumstances have been favourable. (I should own up to more failures than successes on Quarhouse Wall.) I’m trying to compile a list. Measuring their gradients is a task in itself. I use my Garmin Edge 130+ GPS with two satellite networks and a barometric altimeter. Anything less than this is a waste of time. Many of the gradients quoted by cyclists are exaggerated. Perhaps they quote the maximum spot reading of unreliable devices. I’ve made changes to routemaster to improve its ability to estimate gradients from GPS readings. I load the raw FIT file from my device (which records altitudes to quintimetre precision – itself a source of inaccuracy). Then I optimise with ‘90’ as level of detail: the optimisation smooths nearby altitudes, somewhat reducing the error in them. Then, if points are retained so close to each other that there are implausible jumps in gradient (based on my experience of the hill), I delete enough points to make the gradients credible. The gradient I quote is roughly the maximum gradient remaining between two waypoints. There probably remains a 2% uncertainty. The difficulty of a climb depends on its surface, on its maximum gradient, on its length, and on whether the hardest part comes near the beginning or the end. A tailwind helps. Sometimes I find climbs easier or harder than I would expect from any figures I can compute; for instance, I find Thrupp Hill harder than Bushcombe Lane. I list the climbs below, ranked according to my estimate of how difficult I would find them if their surface was in good condition. I include Greenway Lane (Shurdington) although it doesn’t really qualify as a road. The tick column records whether I have ever climbed it cleanly. ‘Asc’ is the total ascent and is rather arbitrary, since several of the routes could be extended to give a longer climb (but with a change of character). Links are to GPS tracks.
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