Langer See

Is open to skating in winter when the ice is thick enough.

good for relaxation at any time of year

The Long Lake is 860 meters long and is crossed by the Harp Bridge. The lake is fed by rainwater from the district via three rainwater treatment basins. Rain that runs off the buildings, traffic and the earth's surface collects in the rainwater treatment basins. Washed-in nutrients and suspended matter are removed from the cycle by the plant growth in the rainwater treatment basins. From there, the water slowly flows into the lake. The lake itself is sealed off from the groundwater and excess water is slowly released into the Schwippe via the Aischbach. The south bank is designed as a reed zone and allows water birds to breed. Conceptually, the rainwater treatment basins and the Long Lake also serve as flood protection.
Source: de.wikipedia.org/wiki/Flugfeld_(Stadtteil)#Langer_See