Over the River Rhine from downtown Koblenz is the Festung Ehrenbreitstein fortress, sitting atop a hill overlooking the surroundings. It is one of the largest fortresses in the world, dating back to 1000AD, and was lived in by the electors and archbishops of Trier from 1648 to 1786. The holy Rock Christi relic was kept here for a period. The Landesmusem Koblenz city museum is located here today, combining the great views and historical building with collections and exhibitions on the history of Koblenz. The Rhein-Museum and its hydrological collections are also housed here.
