I once read there is a castle you can stay in Scotland that is a hostel. Edinburgh this November 2007 is my new adventure
Yes there is. It is Cabisdale Castle up by Inverness and kind of in the middle of know where. I stayed there a few years back. It was ok, but nothing that exciting. I think it was built in the 1800's. I have attached a link.
http://www.syha.org.uk/SYHA/Web/Site/Hostels/CarbisdaleCastle.asp
There are other youth hostel castles. I stayed in one way north of Inverness near Lairg.
Not sure about a hostel castle, but I do know an amazing hostel in Edinburgh, Budget Backpackers in Edinburgh is one of the best hostels I ever stayed in Europe. It has a great location, big nice clean rooms, free walking tour, and pub crawl, I was traveling solo and the staff really makes everyone feel included with extra activities, the kitchen was great and I saved alot of money by making my own meals. I highly recommend this place you can contact me for more info.