Ehrenbreitstein Fortress is a fortress in the German state of Rhineland-Palatinate, on the east bank of the Rhine where it is joined by the Moselle, overlooking the town of Koblenz.
Occupying the position of an earlier fortress destroyed by the French in 1801, it was built as the backbone of the regional fortification system, Festung Koblenz, by Prussia between 1817 and 1828 and guarded the middle Rhine region, an area that had been invaded by French troops repeatedly before. The Prussian fortress was never attacked.
Since 2002, Ehrenbreitstein has been part of the UNESCO World Heritage Site Upper Middle Rhine Valley.