The location of the barn where Jeroen is hiding can be seen in episodes 176, 177, 178, and 179 of season 2 - part 2.
When Jeroen had to flee from Wolf (Raven) during the camping trip, he hid in a barn. The barn's owner wasn't too happy about it.
The barn was filmed as a locker room for the football club F.C. Greunsjotters in Vossem. The building no longer stands.
