[OSM-talk] [Tag] "Ref" in "link"

[Ed Loach]

Xav wrote:

> Well... no reference ?

There is a note at the bottom of the wiki page about the German use
of ref (don't know if it's been added recently). In the UK it is
more likely that if a ref tag is used at all, then it will be the
ref of the motorway that is used as motorway restrictions apply on
the link (or slip) roads. In the case where two motorways join then
there is probably some arbitrary point where the way stops being one
motorway and starts being the other - I'd probably not add a ref on
the way in this case. 

The tag highway=motorway_junction has also been used on trunk roads
in the UK that have had their junctions numbered (this used to be
rare - I'm not sure it is quite so rare any more). One example is
where the A12 and M25 meet - the M25 junction is J28 but the A12
junction is J11. The nodes where the slip road leave the main
carriageway get the junction ref relevant to that way. I'm not sure
whether this is relevant to your question though - perhaps it should
just have been highway=junction so it could be used on all ways
without people worrying too much about the motorway_ in the name.

http://www.openstreetmap.org/?lat=51.60859&lon=0.26331&zoom=16&layer
s=B000FTF

Ed

PS: I've just realised that the J11 nodes weren't tagged so have now
done so. They may not yet have been rendered if you view the above
link.