Uninhabited
Börnicke Castle

Schloss Börnicke, a manor house in Brandenburg, stands out due to its unusually modern architecture for its time of construction. It is located in Börnicke, a district of Bernau near Berlin, and is surrounded by an extensive park with a small lake.
History+
The castle complex was built between 1909 and 1911 on behalf of the Berlin banker Paul Robert Ernst von Mendelssohn-Bartholdy. Architect Prof. Bruno Paul created a well-proportioned building that distinguished itself from the then-common ornate Wilhelminian style. After the builder's death in 1935, the castle was briefly used in 1945 by members of the Swiss Embassy seeking protection from the bombing raids in Berlin. In April 1945, Soviet troops established a hospital in the castle.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Boernicke_Schloss.jpg
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 52.6621, 13.6334