Rocking'Robin: regarding alternative campsites, there are a couple up the hill past the observatory.

I use the one on the left, it appears on the internet as a golf course: http://www.thorngolfcentre.co.uk/ . This site is used by lots of fringe festival goers (like me). Although it's fairly basic it's kept clean, has showers & loos....and it's not expensive. There's a regular bus service into town and back so you can safely fill up with beer in town.

We'll be there in our titchy caravan towed by a silver-grey Fiesta - come and say hello!

John