Especially at famous, obvious, I'm-deliberately-visiting-it sites like Silbury and Stonehenge. You don't climb up Silbury thinking it's an ordinary hill. You don't stand on the lintels at Stonehenge without knowing where you are.
Does anybody know of anyone who was actually taken to book over climbing Silbury! What actually would they be charged with? You can't claim trespass as I believe by law you have to state this on signboards - Silbury's don't say that do they! And how could they claim that you damaged the site just by walking up it. A good lawer would have it thrown out after naming all the official bodies, TV crews and archo's that had walked up there in the past. What did they do, wear slippers?
This is TIC by the way (g)
This isn't about the law. If Silbury was impervious to the human foot I would fight for the right of everyone to stand on her summit.
I agree that one peron walking up Silbury will have virtually no effect, but multiply that by potentially thousands per year and you have serious erosion problems.
Let me explain properly, from example. Take a mountain in the Lakes, North Wales, or Scotland. Many are experiencing serious erosion problems due to the amount of people walking up them. Many involve quite a bit of effort to get up, unlike Silbury, whose top is of easy access from the road.
Now consider the effect of a path worn into the hill, lets say around six inches deep into the top soil and chalk, which is small compared to the mountain areas I've quoted. This isn't only a path for feet. It's also a path for water, and ,when it rains, the water will take the line of least resistance, like it does in the mountains, and will erode the path up Silbury at an alarming rate. I have witnessed this first hand many times in the hills, and the rate of erosion is quick. If this was to happen at Silbury it would potentially erode the archaeology under the top soil, and get deeper with the years.
I hope this explains the concerns of Rhiannon, et al, who have challenged your post.