Johannesthal was formerly part of the German Empire. In the German Empire, the place was called Johannesthal.
The place is now called Janův Důl and belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Johannesthal | Austro-Hungary | Böhmisch-Leipa | before the Treaty of Saint-Germain |
| Janův Důl | Austro-Hungary | Böhmisch-Leipa | before the Treaty of Saint-Germain |
| Janův Důl | Czechoslovakia | Česká Lípa | after the Treaty of Saint-Germain |
| Johannesthal | Czechoslovakia | Česká Lípa | after the Treaty of Saint-Germain |
| Johannesthal | German Empire | Reichenberg | 1938 |
| Janův Důl | Czechoslovakia | Liberec | 1945 |
| Janův Důl | Czechoslovakia | Liberec | 1992 |
| Janův Důl | Czech Republic | Liberec | 1993 |