Ffordd_Pen_Llech is steep but it's one way (down), so if you're looking for challenge to go up it on your bicycle you have to do so illegally.
Apparently Vale Street (http://www.openstreetmap.org/way/32024547) in Bristol is meant to be very steep, but I don't know the incline. (Doesn't seem to have incline posted looking at GSV. DaveF: Was this the road you were thinking of or something in Bath?) The posted incline (at least in the UK) is the maximum gradient. This is also the definition used in OSM, see https://wiki.openstreetmap.org/wiki/Key:incline Note that they mostly seem to be signed as 20%, 25% & 33% & 40% - so mostly a percentage version of the 1 in 5, 1 in 4, 1 in 3 gradients. Thus you don't tend to get gradients of 22%, 23% etc... So it seems the posted value is often rounded one way or another and certainly cycling up differing hills I've found some seem easier/harder than expected given the signed value. An interesting list of steep roads is here: https://roadcyclinguk.com/sportive/ten-uks-steepest-climbs.html/ Previously this steepest road question has been pondered several times. One interesting thread is here: http://www.intelligentanswers.co.uk/index.php?topic=2962.0 Notionally the average gradient could be worked out fairly easy with reasonable SRTM or better LIDAR data or possibly given a number of GPX files to analyse - although I don't know whether any of these methods would give an accurate enough answer to be of comparable use. Certainly for shorter (i.e. residential rather than long mountain/big hill climbs) road (such as Vale Street) the margin in error of the elevation readings will be considerable compared to the road length such that the calculated gradients could be very unreliable. Some work on trying to auto calculate gradients can be found here: https://github.com/nautoguide/gradient_markers -- Be Seeing You - Rob. If at first you don't succeed, then skydiving isn't for you. ________________________________________ From: Dave F <davefoxfa...@btinternet.com> Sent: 11 January 2017 22:04:03 To: talk-gb@openstreetmap.org Subject: Re: [Talk-GB] the steepest residential street in England On 11/01/2017 18:18, Jez Nicholson wrote: > Google is telling me Hardknott Pass and Rosedale Chimney Bank at 33% > for England. > > They used to do hill-climb car racing up Porlock Hill in Exmoor but > that is reported as a mere 25% > > I can't help but think that there are some short side-roads that are > steeper. They may also have further criteria for the 'World Record'. > Indeed, "criteria" is paramount. Porlock & one in my vicinity is marked as only 25%. I'm pretty sure sections within them are a bit steeper than that. Can anyone clarify that it's an average over the whole rise or the maximum gradient? DaveF. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus _______________________________________________ Talk-GB mailing list Talk-GB@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-gb _______________________________________________ Talk-GB mailing list Talk-GB@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-gb
