Hrádek was formerly part of the German Empire. In the German Empire, the place was called Hradek.
The place is now called Hrádek and belongs to Czech Republic.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Hradek | Austro-Hungary | Dux | before the Treaty of Saint-Germain |
| Hrádek | Austro-Hungary | Dux | before the Treaty of Saint-Germain |
| Hrádek | Czechoslovakia | Duchcov | after the Treaty of Saint-Germain |
| Hradek | German Empire | Bilin | 1938 |
| Hrádek | Czechoslovakia | Louny | 1945 |
| Hrádek | Czechoslovakia | Louny | 1992 |
| Hrádek | Czech Republic | Louny | 1993 |