There is a meadow located at the edge of Aveyron which offers a tranquil setting. While this land is privately owned, the owners do allow short stays of 1 to 2 nights as long as the path remains unobstructed and visitors show respect for the area.
The river is beautiful and the spot is nicely shaded. However, we had an unfortunate experience as there were too many people parked inconsiderately and leaving litter near the water. These behaviors are the reason why we no longer feel welcome in many places.
I visited around 10/09, it was a peaceful place but had limited space. There is a market in Nègrepelisse on Tuesday mornings, a 5-10 minute drive away.