Hi Rhiannon,
Please bear in mind that I haven't read most of the replies. This is my reply to your original post:-
I can accept a request to not climb a "sacred hill" due to erosion problems, such as Silbury Hill. However, I find it hard to comply with the religious reason.
How can a religious reason be reason enough to keep people off a hill, unless you belong to that religion? What if I suddenly decided that Scafell Pike, Ben Nevis and Snowdon were integral to my religious beliefs, and that I didn't want anyone to climb them? I can't see anyone complying with my wishes. So, what's the difference? Can't see one myself.
Basically, we can't expect everyone outside our own specific belief system to respect it. If I was requested to keep off a particular hill on a certain day to respect a religious belief, then I would respect that. After all, it's only one day.
All the best,
TE.