NN was formerly part of the German Empire. In the German Empire, the place was called NN.
The place is now abandoned and the area belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Wrtwa | Austro-Hungary | Kralowitz | before the Treaty of Saint-Germain |
| Vrtva | Austro-Hungary | Kralowitz | before the Treaty of Saint-Germain |
| Vrtba | Czechoslovakia | Kralovice | after the Treaty of Saint-Germain |
| NN | German Empire | Kralowitz | 1939 |
| NN | Czechoslovakia | Plasy | 1945 |
| - aufgelassen - | Czechoslovakia | Plzeň-sever | 1992 |
| - aufgelassen - | Czech Republic | Plzeň-sever | 1993 |