Grum technical I suppose that as a road climb Cragg vale is the longest as the one to the top of Cross Fell is a Bridleway which has been tarmacked to allow access to the air traffic control stuff on the top.
Cross Fell is probably the only Cat 1 climb in the UK.
The road to the radar station on Great Dun Fell [edit – not Cross Fell Dales rider] is the biggest vertical drop on tarmac IIRC, it’s not a public road but is a bridleway, and there are longer descents with less vertical drop. A good climb, but Cat1? I dunno about that.