suggestion for caravan sites in france

Hi we don't want to travel too far from Calais or dunkirk but don't want to be at the sites closest as people seem to suggest there is a lot of activity coming and going as people use them for only 1 or 2 nights. But somewhere without a huge drive. i get sea sick so can't go on a longer boat journey!

we are looking for somewhere not huge but with pool and shop if poss and somewhere a teen can hang out. Has anyone any sites they found particularly nice? thanks