We have a local narrow bridge which is about 50 yards long on the road out of a village. At one time there was two way traffic with no provision for pedestrians, and passing vehicles managed, though if a bus or HGV crossed, there was no room for a car to get by. Generations of scrape marks on the stonework testified to the wisdom or otherwise of letting drivers decide for themselves. A few years ago a pavement was laid along one side of the road, making the bridge single lane and priority signs were installed. Possibly this had as much to do with reducing the weight on the bridge at any one time as consideration for pedestrians.Traffic leaving the village has priority. There are good sight lines at each end. The sign means "Priority to oncoming vehicles", with no ifs or buts. I would think, legally, that oncoming drivers are in the wrong if they think they can push through but it often happens that following traffic will follow someone who does it, leaving priority traffic having to wait until the oncomers have passed. I have also on several occasions recently seen oncoming traffic reversing if they are the only vehicle, when they realise that traffic from the village is waiting. Often, though, if the first oncoming vehicle sets off, following vehicles will fill the space they have left, giving no option for them but to press on. The majority of drivers follow the rules, as there's nowhere to go if two vehicles meet on the bridge.
When it comes to bike vs car I'm not aware of any issues. Round here, at least. cyclists seem to be acknowledged as part of the traffic by most drivers. If it comes to a Mexican stand off, the car driver has a bigger gun than the cyclist, and it would be a bold rider who would insist on their right of way against some motorised chancer. If it came to the worst, the cyclist could become a pedestrian and wheel their bike along the pavement. In many places there is only the narrow road perhaps walled in by a parapet each side. It is even more important for drivers to follow the rules in this situation, assuming that they know them in the first place.
