Eger Graben
The Eger Graben (Czech: Oherský příkop, German: Egergraben) is a geographical unit in the Czech Republic. It runs southwards, parallel to the Ore Mountains (Krušné Hory) and its formation is linked with that of the mountain range.
Topography
The Eger flows through the Eger Graben and separates the Ore Mountains from the Kaiserwald and the Doupov Mountains. The trench continues to the northeast along the valley of the Bílina and later, as the North Bohemian Basin, separates the Ore Mountains from the Bohemian Central Mountains, where the River Eger leaves the graben and flows into the Elbe south of the Bohemian Mountains.
Geology
The Eger Graben is part of the European Cenozoic Rift System and was created geologically on the same principle as the Rhine Rift Valley. It was formed by the almost complete erosion of the Variscan Mountains and sits on a fault-block caused by the horizontal pressure of the African continental plate. This block dropped, however, in contrast to the surrounding area. The Ore Mountains are fault-block mountains which rise very gently in Germany, but drop very steeply into the Eger Graben. The trench thus follows the main fault line of the Ore Mountains.