GeoGraph - photograph every grid square

Let's make this clear

The signs might seem forbidding, but they actually make the situation very clear. It is a private driveway, therefore no vehicles except for access, but for those vehicles that are allowed access the sign reminds drivers to look out for horse riders and walkers. That is because it is a public bridleway, which means pedestrians, horses and bicycles may use it, and the Oxfordshire County Council sign reminds vehicle users that it is an offence to drive down a bridleway without lawful authority.
The route is part of the Thames Path National Trail, so it is well used, hence the clarification.