In reply to GL:
I spent a month at Camp 4,
the rules say that you can only stay there for a week at a time.
when it came to check-out morning we just registared again for another week under another name.
my tent didn't move for the month.
I known there were some other Brits who had sold a house and were touring around the States for a year.
the bought a RV and didn't seem to have any problems, but you'll have to check on that.
Tuolomere Meadows is great and alot quieter than the Valley, we were only there for a couple of nights, so I can't comment about that
have a good trip