[Talk-GB] Advice please: Goat tracks in mountain areas

[David Woolley]

On 05/02/2022 14:26, Gruff Owen wrote:
> 
> It has been tagged as:
> bicycle:no
> highway:path
> horse:no
> 

What would initially concern me is that bicycle=no and horse=no probably 
represent the mapper's view of its suitability, and are therefore very 
subjective, which is wrong.

Not mapping it would be wrong.  The correct way is to provide 
attributes, e.g tracktype=Grade 5; surface=ground; width=70cm; 
smoothness=horrible; sac_scale=difficult_mountain_hiking, that allow a 
router to make its own judgements (although some of these could also be 
considered too subjective).  I'm not sure though, to what extent routers 
actually look for such contraindications, but there is a principle that 
you do not tag for the renderer, which means it is the router's job to 
assess suitability and one must not try to influence it by misdescriptions.

Pyg Trail, to which this path is attached, is classified as 
sac_scale=mountain_hiking, in OSM, which is the second least onerous. 
The description for sac_scale says that paper maps often do not include 
paths with the most onerous values.

Total omission doesn't work, if the feature is visible, because people 
will, eventually, remap it.