Driving directions from Chantilly to Campix: take D-44 to the west [and slightly north] from Chantilly . In about ten minutes one crosses the Oise river and enters the commune of Saint Leu d’Esserent, which is noticeable from a distance by its large abbey. The road direction signs to the campsite route you around the southern edge of town to the west, where you turn north on to D-12.
The route takes you just north of town. As you are about to leave the built-up area and come to large, open farm fields, you turn right [east] and wind around a very small [but with good directional markings to the camp] route to Camping Campix.
GPS users, attention: If you enter the official address of Camping Campix, Chemin des Carrières, you will be directed to the wrong side of the camp site, where cars are not allowed. Once in St Leu: ignore the instructions of your GPS. Just follow the signs to Campix.