No unauthorised access

Swinley forest today - don't you just love walking up behind a large set of metal barriers to find a sign on the other side prohibiting unauthorised access. Of course, nobody was taking the blindest bits of notice and calmly walking around to walk along the trails beyond.

As a sign writer I always find this road sign an amusing one. I always imagine that the cartoon builder is obviously shouting 'Oi!'. But despite the fairly complex message, you have to admit it is a sign that is hard to misinterpret.