Anyone been riding in North France / Belgium - within 2 to 3 hrs from Calais?
After is stuff that is comparable to say Afan or Llandegla or Coed y Brenin etc.
There's loads of stuff in the Ardennes, none of which I've ridden but I've heard good things. there's not really any trail centres though, it's not really a thing around this neck of the woods so you'd need to strava or check local forums for info.
If you're planning on being there at the start of May, there's also this: http://www.sport.be/rocdardenne/2014/fr/
I think there is a trail centre but I have no idea if it is any good as I've never been, sorry
http://www.filthytrails.be/EN/INDEX/index.php
Lac Blanc in teh Alsace is the closest bike park with uplift i think
There's another bike park in the Ardennes which is supposedly good. It's only an hour away from me but I tend to go to Lac Blanc (2 hours away) as a rule.