In reply to GPN:
Cave Route Right (7b+)? One of the best of its grade in the country.
Both Cave Routes are great routes and mega lines but don't actually require much full on crack climbing technique.
For bolted cracks in the north of England its hard to beat the 3 at Lorry Park, proper crack testpieces and really good, in particular Supercrack (Sport) (7a) which fully deserves its 3 stars.
At the same crag On the Road (Sport) (6c+) is more of a crack in an overhanging corner requiring laybacking and bridging rather than full on crack climbing but is excellent, very imposing and gives great physical climbing.
Post edited at 14:44