In reply to seankenny:
Pretty much yes, surely the best possible way to research information about "good sport climbing destinations which are accessible without renting a car in Europe" is to ask a question on UKC, where there are many people who are highly knowledgeable about the subject?
It's difficult to gauge if the author of any information online has any vested interest in the crag they are all telling me is amazing/better than the next crag. Sometimes, there's a lot of conflicting information, especially if the crag has been allowed to deteriorate.
Thanks to anyone who has suggested any ideas. As someone pointed out, I forgot to mention when I was planning to go. I'm hoping to go either around Easter time or later on in the year, around about June (which rules out quite a few places due to the heat)