The GCU Auvers-sur-Oise campsite has limited availability during low season, except for July and August. During this time, you can only contact someone between 8:30 a.m. and 9 a.m. or 6 p.m. - 7 p.m. Outside of these hours, the campsite is closed and not accessible.
I stayed at a great camping site for 6 weeks for work. It was really peaceful there. The campsite is maintained by the campers themselves, which is why the cost is low. It is a community-run campsite, so the manager is only there for 1-2 hours each day. The manager is very friendly and accommodating. The sanitary facilities are new and the location is really convenient.
We went there but once we arrived, we found out that they have limited hours during the low season, except for July - August (8:30 AM - 9 AM and 6 PM - 7 PM). It was impossible to reach anyone outside of those hours. It's a pity because it seemed nice, except for the neighbors' dog that likes to bark.