A solution I have found works (in my mapping of both biking and hiking trails and mixed-use bicycle-pedestrian trails) is to tag highway=cycleway if it is primarily for cyclists, including foot=yes or foot=designated to indicate pedestrians are allowed. Though, in this case, who has right-of-way might be defined by signage or law, but isn’t well-defined with this tagging.
Conversely, for pathways which are primarily for pedestrians yet also allow bicycles I tag highway=footway + bicycle=yes.
The inclusion of other “travel modes” or “access permissions” like horse=no is a good idea if known, but it isn’t strictly required.
To be clear, I sense some confusion on using only one value of (route=) foot, hiking or bicycle on a relation of type=route. You want certain / largely these tags on the ways (“infrastructure tagging”). THEN, collect these ways together into a single relation of the appropriate kind of route (foot, hikingbicycle…): “route tagging.” If it is the case that there are more than one route (a hiking route and biking route) which include similar or identical ways, then use more than one route relation, using the correct way elements multiple times in each route relation as necessary.
If it looks like a what we call a bikepath, ie paved, heavily used by bikes I’d tag it highway=cycleway. To be complete add surface=paved, foot=yes, and motor_vehicle=no (& horse=no if that’s the case). Bikes yielding to pedestrians is the norm, so there’s no need to try to come up with something for that.
I wouldn’t put route on a way, it’s usually used for relations.
If cyclists must yield to pedestrians I think that might push it in favour of foot=designated and bicycle=yes with either a path or footway tag. They actually might both be designated, but it feels like in this case ‘some are more designated than others’.
Yes, @InsertUser, I agree. If it is true that bicycles must yield to pedestrians, I tag foot=designated. Of course, if horse=yes is also true, we might say “horses are designated,” as pedestrians yield to horses (in my jurisdictions). For this, now we change into highway=bridleway, so it can be sort of tricky when you fully apply the “intention of the road” and access restrictions (or permissions for mixed traffic) with right-of-way. But between “only” bike-and-ped (no equestrians), we agree.
We probably have 1000’s of miles of trails in the western US that are tagged quite properly as highway=path. Access (foot/bike/horse), is usually wide open (exc wilderness areas) (often dirt bikes too). The yielding hierarchy is not signed everywhere, but it is implied (horse-foot-bike), usually common sense & politeness prevail & the yielding hierarchy is not strictly followed. No reason to use the odd footway/bridleway tags for a multiuse trail.
In regards to designated: Many trails are designed for and built by mtn bikers, but bikes should still yield to hikers, who should have the designated tag? It may be useful some places, but It’s a meaningless tag to me.
Most of the responses seem to be talking about tagging the way whereas the OP, I think, was talking about tagging the relation.
It’s fairly common, on the east coast of the US at least, to have a semicolon-separated route= tag in a relation. So you might see route=bicycle;foot or something like that.
Data consumer support for that is not universal, however.
The alternative is to create two relations, one with route=bicycle, another with route=foot (or hiking or whatever).
Thanks, @Richard: it looks like we agree, as we seem to be saying the same things (I in my post beginning “A solution…”).
It does seem that the OP needed some sharpening up of what United States/Bicycle Networks - OpenStreetMap Wiki distinguishes between “infrastructure tagging” (what Richard just called “way tagging”) and “route tagging” (tagging the route relation). Each of these (for good reasons) and both of these (so they work together) are both important and distinct to tag properly. This is not tagging for a particular renderer, it is just plain good tagging for OSM!
One more thing, there are instances where something likebicycle=yes is recommended to be put onto a route=bicycle relation (though I agree it is more intuitively useful on ways): the noted wiki says to do this where there is a certain type of (generic) “Bike Route” sign, so the wiki suggests “OSM ways so signed as local bike routes should be tagged lcn=yes, either directly or as members of a network=lcn relation tagged lcn=yes.”
The point is it is important to understand and implement the difference between tagging ways and tagging relations.