With the help of Sustrans volunteers and the OSM community, Simon Pratt is leading a task to resolve differences between Sustrans and OSM mapping of the UK National Cycle Network.
Sustrans has created an interactive map showing the differences between Sustrans and OSM National Cycle Network mapping. Currently there are several hundred of these differences.
Simon Pratt worked for Sustrans for 28 years, most recently as Head of Network Development UK, where he led the creation of the Network Development Plan for the NCN. Simon is now leading the task of resolving the largest differences between the two geodatabases, Sustrans and OSM mapping.
How can I get involved?
Checking the map yourself
You can view the Sustrans differences map for your area and start to make changes yourself in OSM. There is a direct link from the features on the map to OSM for ease of editing. If there are changes that you think need to be made to Sustrans NCN mapping, please contact Simon in the first instance. You can also draw a polygon around the feature and post your comments.
Look out for a map note in your area.
Simon will be making minor changes to Sustrans and OSM mapping himself where the errors are obvious. But, where a decision is needed, Simon will get in touch with people in a specific geographic area to help resolve the issue using a map note.
More information is available at this OSM wiki page. Please note that a buffer of 100 metres has been used between the two datasets, so that only the larger differences are included.
This task is for the whole of the UK and is likely to take several months, but Simon has started in the South of England as he is more familiar with the region, and then work his way across the rest of the UK.
I had a quick look in an area near me and found a way in OSM that is highlighted on your map as “Sustrans NCN does not align with OpenStreetMap” which means “This feature is drawn in Sustrans data but not in OpenStreetMap.”, yet as I’ve linked, the feature is in OpenStreetMap.
I then thought it must actually be “might be in OSM but not tagged in a way we recognise”. But it’s tagged similarly to a segment which seems to be fine according to your map.
So I was a bit confused and was going to report it via the feedback button. But that takes me to an editor which wants me to “create a new feature” and that’s totally unclear what I’m supposed to do there. So I gave up and thought I’d post here instead!
Just to note that in general OSM mapping should follow the ground truth (i.e. where the signs on the ground actually direct the route) rather than what the official Sustrans map says the route should be. Of course, the two will normally be the same. But in the event of any discrepancies, OSM would usually follow what the signs on the ground say - until they’ve been fixed.
The feature in Stechford is shown in OSM, but not as NCN. It is tagged as the Cole Valley Route, a local cycle route. To report an issue in the Sustrans map, you need to draw a polygon around the feature and you can then write your text.
I’ve just had a look at one issue near me, in Downham Market. Currently in OSM RR30 and NR11 follow different routes through/around the town centre. The Sustrans map just shows the straighter Eastern route.
IIRC correctly, the Western route was the original one, so I’m guessing that it’s been re-routed more recently, and only one of the two OSM routes has been updated.
However, looking at Google Streetview (which isn’t a permitted source for OSM editing, but can be useful in discussions like these) it seems that both routes may actually be signed on the ground. (Or at least they were in April 2023.) I can’t quite make out the text on the signs, but perhaps one is the main route and the other is an alternative “via town centre” option. See
If those signs are still in place, then probably OSM should have the main route mapped on the eastern route, with the other part mapped as a link or alternative route. I don’t know if that’s how it’s suppose to be, but it would be helpful if the signage or Sustrans mapping could be updated so those two match. Then we can make OSM consistent with both of them.
I don’t know the background to this one, but Sustrans has mapped the eastern route as the “main route” since 2005. I can’t see any value in retaining the western route and my instinct would be to remove it from OSM and ask local volunteers to remove the signs (or cover the number patch). There may also be cases where the route number is shown in brackets i.e. a link leading to the NCN. Some may be mapped as Sustrans NCN and others not.
To your earlier point, there can be a delay of months or years from a decision to remove or realign a route and the signs changing on the ground. I totally understand that OSM mappers want to record what is in place.
Locally the use of brackets can be a bit … irregular. As an example, this overpass query shows the main route of NCN65 with markers without brackets as green and markers with brackets as yellow. Some of the outliers (like the one at Thirsk Station!) are very much “out”.
where there is a big gap in the Sustrans routes 14 and 70. I don’t recall seeing any local signage to indicate that the gap IS part of the Sustrans routes, but it would seem very wrong to take this chunk out of the relevant route relations!
I’m assuming this is some kind of legal matter where Sustrans have no responsibility for the “gap” (which will be a council maintained cycleway).
But this will be of zero interest to (map) users.
I can’t see an obvious reason why this route section is not shown on Sustrans mapping and it is shown on the 2023 County Council map. I will investigate further.
Road works in this area have only just been finished. there is a bit of a signage mess in cefn coed in the top right. the signage on the ground indicates both paths being correct but Sustrans only has the north path.
As a compromise I tagged the north path as link route rather than a full however on the ground it is signed fully as the 46 however it dead ends on the east side where it meets the roads and there is no further signage.
Thanks, I have passed your messages on to Sustrans. I can confirm that Sustrans is aware of the issues with NCN46 and will update NCN mapping in the next few weeks.
Sustrans cancelling many miles of routes is its own decision. If the signs really are removed (ex Sustrans volunteer here, who won’t be volunteering to undo my own work), then in due course OSM can reflect that.
I would emphasise what’s been said already: if the route is signed on the ground, it should be in OSM. If Sustrans doesn’t like it, that is not an OSM problem.
Harrumph.
EDIT: The text on the Sustrans diff map is explicitly opposite to OSM policy, and encourages edits that break the ground-truth rule.
Suggested Action: This feature is drawn in OpenStreetMap data but not in Sustrans data. If you think this is an error, use the link below to correct OpenStreetMap. Alternatively, use the feedback button (below) to notify the Sustrans Network Development team if you think it’s missing from Sustrans data
It doesn’t matter for OSM policy what someone “thinks” about a route. The important thing is what they have observed on the ground, or on some other ground-truthed source.
Well, it’s complicated isn’t it? In some places it’s really obvious where the route goes, and that there’s only one route, and in some places (see my NCN65 link above) there really isn’t.
Where there isn’t, someone has to have a “best guess” about where the route “is probably supposed to go”.
I’ve marked up some of the “differences” near me; they’re mostly due to rerouting not “deNCNing”. In the most recent case new signs have been put up but old signs have not been taken down (not necessarily Sustrans’ volunteers fault - the affected road may well have been closed at the time).
One “deNCNing” one that will need visiting (to see what signs exist) is near Sutton Bank in Yorkshire. From memory there is a verge there, but I’d never consider cycling it because I don’t have a death wish. I can understand why Sustrans don’t want to consider it NCN. Unfortunately that then leaves the problem of getting from one minor-road part of the NCN to the other - there are no easy answers here.
Fair enough. Round my way the diffs are all (without exhaustive audit) deNCNing ones. I know the route I travel most often is still signed.
Sure. I see that as a Sustrans matter. I don’t think we should be harmonising the database with Sustrans data, rather than with the ground. Edit: and to be fair you expressly said ground check was needed; but the ref to Sustrans’ wants is surely irrelevant?
Thanks. Can you maybe clarify what the aim of your project is? (I assume you are the Simon Pratt referred to in the third person in the OP.)
Is it - as I have understood it, and putting it shortly - to see to it that OSM is a copy of the Sustrans GIS? That would seem to be what the wiki page says:
Unfortunately, it has taken much longer than planned to change the signs on the ground and there are still some differences between the Sustrans NCN mapping and the signs with a red number patch designating a NCN route.
Is this saying, “Despite the presence of a red patch, if Sustrans say it’s not NCN, OSM should not say it’s NCN”?
