Parc Departemental du Sausset, Aulnay-sous-Bois

Nice open space, plenty of activities. Gym, boat house, fields, biking, plenty of benches. They really need to clean up the place though. Maybe start ticketing litterers or have some groups come through and give the place an overhaul. The Louis Vuitton museum is right door, perhaps the worlds largest luxury and spirits conglomerate can afford to clean up a park.

This is a beautiful park about 6km by walk from Roissy-en-France. (1.5 hrs walk one way or about 30 minutes by cycle.) it’s a combination of of a park, a lake and a wooded area. Good for birding 🦅. Also you get to see hares 🐰 every now or then. I suggest going during day time as during evenings it gets deserted. The lake at one part is natural and beautiful where you can find a small island with many birds. It also has an open gymnasium. One can comfortably spend a few hours in the midst of nature. There are tracks in the wooded area. I happened to see an owl there once. You can walk or cycle within the park.