Former garbage dump. Right on the water. Designed as a park and recreational area and the only "rubble cave" known to me that is a listed building. Concrete blocks and broken glass still come out here and there. Worth seeing.
You can only walk around the lake in summer, when the paths are dry. Otherwise you have to stay on the paved paths. The lake is full of birds and many people pass by carelessly. It's worth taking a look.