OpenStreetMap
I just surveyed a hiking trail in my neighborhood (U.S.). It appears that part of the trail used to be a public road (dirt surface single lane), but is now closed to public traffic. OSM has this part of the trail tagged as a road (presumably because it was imported from TIGER). Shouldn't features (ways) be tagged according to their present legally permissible use, rather than the type of use they physically might accommodate?
Discussion
Comment from Jean-Marc Liotier on 17 гыйнвар 2010 сәгать 18:47
Yes, features must represent the current reality.
Here is how I would tag that one :
highway=unclassified
surface=dirt
motorcar=no
lanes=1
Comment from 42429 on 17 гыйнвар 2010 сәгать 18:54
You are completely right:
highway=track, tracktype=grade3 (dirt) would be the right tagging for such a former road without motorized traffic. Depending on the surface, you may change the tracktype to grade2 (fine gravel) or grade4 (rough earth).
osm.wiki/Tracktype
However, it will take centuries to check all rural roads in the United States for their tracktype, so you can't expect to see this tag everywhere in the United States. In Europe, tracktype tagging is much more common as you can see here:
osm.org/?lat=53.491&lon=8.7187&zoom=14&layers=B000FTF
Comment from wallclimber21 on 17 гыйнвар 2010 сәгать 19:00
In addition, you should tag it as
access = private
Comment from 42429 on 17 гыйнвар 2010 сәгать 19:08
highway=unclassified is a tag for public roads. unclassified roads without motorized traffic are very rare, maybe within national parks.
Using the tag motorcar=no would still allow motorcycles to use this way.
Motorcycles and snowmobiles (and horses) need a separate tag.
Tracks are closed for motorized vehicles by default. However, farmers are often allowed to use these tracks, but farmers don't check Openstreetmap in order to find their fields.
Comment from 42429 on 17 гыйнвар 2010 сәгать 19:13
Sorry, I have to comment this suggestion:
access=private is valid for all visitors, e.g. hikers.
access=private means NO trespassing (except for patrons).
motorcar=private would exclude cars, but no hikers.
Comment from ulfl on 17 гыйнвар 2010 сәгать 19:46
"Tracks are closed for motorized vehicles by default." depends on your local jurisdiction, which differs e.g. here in germany even between our states "Bundesländer".