The fundamental idea of the Right of Public Access is that you may roam the countryside without regard to land ownership. Landowners are therefore not allowed to put up fences to keep people off land that is subject to the Right of Public Access.
If a cattle fence prevents the public from reaching an important outdoor recreation area, the county administrative board may order the landowner to provide a right of way, such as a gate or stile. Similarly for ditches: the county administrative board may order the owner to provide a footbridge across a ditch that obstructs public access.
You may climb a fence to reach land that is subject to the Right of Public Access. If a fence has been erected for the sole purpose of keeping the public out, the municipality or county administrative board may order the landowner to remove it. However, you are not allowed to take the law into your own hands and cut a hole in it.
Landowners sometimes attempt to keep the public off their lands by putting up signs like Privat mark (‘Private land’) or Ej obehöriga (‘No trespassing’). Signs like this which exclude the public from significant outdoor recreation areas may only remain in place with the permission of the municipality.
The same goes for signs purporting to prohibit walking, cycling and horse riding on private roads.
Landowners may put up signs to exclude visitors from areas where it is obvious that the Right of Public Access does not apply. No permission is required for this. The areas in question are mainly those protected under the provisions of the Swedish Penal Code relating to the grounds of houses, cultivated ground, and ground which is particularly vulnerable to damage.
Signs warning of real dangers are also allowed, such as a "Varning för tjuren" (‘Beware of the bull’) sign on the fence of a field enclosing a bull. In exceptional cases, signs to restrict non-motor traffic may be erected on a private road.
If you come across an illegal sign you are not allowed to take it down yourself. It is up to the municipality to ask the landowner to remove the sign, and it may order him or her to do so under penalty of a fine.