In reply to alps_p:
This crag
http://www.ukclimbing.com/logbook/crag.php?id=8162 is close to the road, south facing, fully bolted and mainly single pitch. If I recall correctly, not that many of the routes have the "swiss-cheese" features, though. Very pleasant place to climb, even though it's only a tiny fraction of the available rock in the area and you might not want to spend a whole week there. Late spring should be fine: I went in early June and despite the altitude it was a bit too hot, and somewhat prone to afternoon thunderstorms.