Fennsee
The following lakes bear the name Fennsee
- Fennsee (Westhavelland) : in the Westhavelland nature park , municipality of Stechow-Ferchesar, district of Havelland, Brandenburg, Germany (between Ferchesarer See and Trintsee, northeast of Rathenow)
- Fennsee (Wilmersdorf) : in the Wilmersdorf district, Charlottenburg-Wilmersdorf district, Berlin, Germany