Hi,

This type of problem was recently discussed on the UK section of the OSM Community Forum. I've linked to the post I made because it has a few links. The discussion went off-topic.

https://community.openstreetmap.org/t/marking-a-prow-as-a-bad-idea/113487/6

A public right of way is a "right" not a physical highway. If there is no "way" for the PRoW to be followed, then I'd suggest the PRoW tagging should still be added but to a way tagged with highway=no.

Two personal examples, which I've just updated.

First is PRoW Bridleway route in Dartmoor that is now within the expanding Foxtor Mire. Is not used and obviously "Hazardous" to cross this bog. Tagged.

highway=no
hazard=wetland
designation=public_bridleway
horse:physical=no
foot:physical=no
bicycle:physical=no
prow_ref=Dartmoor Forest Bridleway 34
smoothness=impassable
source:prow_ref=devon_county_council_prow_gis_data
surface=bog
trail_visibility=no

Second, example is bridleway that can not be used because a large section is obstructed by impenetrable gorse, heather, bracken. Hazard becomes "obstacle". Tagged.

highway=no
obstacle=vegetation
designation=public_bridleway
horse:physical=no
foot:physical=no
bicycle:physical=no
prow_ref=Manaton Bridleway 8
source:prow_ref=devon_county_council_prow_gis_data
trail_visibility=no

