Ehrenbreitstein Fortress Ehrenbreitstein Fortress ( German : " Festung Ehrenbreitstein " ) is a fortress on the mountain of the same name on the east bank of the Rhine opposite the town of Koblenz in the German state of Rhineland - Palatinate . It was built as the backbone of the regional fortification system , Festung Koblenz , by Prussia between 1817 and 1832 and guarded the middle Rhine region , an area that had been invaded by French troops repeatedly before . The fortress was never attacked . History . Early fortifications at the site can be dated back to about 1000 BC . At about AD 1000 Ehrenbert erected a castle . Its initial name " Burg Ehrenbertstein " became " Burg Ehrenbreitstein " . The Archbishops of Trier expanded it with a supporting castle " Burg Helferstein " and guarded the Holy Tunic in it from 1657 to 1794 . Successive Archbishops used the castle ' s strategic importance to barter between contending powers ; thus in 1672 at the outset of war between France and Germany the Archbishop refused requests both from the envoys of Louis XIV and from Brandenburg ' s Ambassador , Christoph Caspar von Blumenthal , to permit the passage of troops across the Rhine . However , in 1794 , French revolutionary troops conquered Koblenz ; in the following years they besieged Ehrenbreitstein three times without success . But a one - year siege , starting in 1798 , brought starvation to the defenders of Ehrenbreitstein who finally handed over the fortress to French troops in 1799 . By the treaty of Lunéville , the French were forced to withdraw from the right bank of the Rhine . Hence , they dismantled Ehrenbreitstein in 1801 to prevent the enemy from taking hold of a fully functional fortress just a few meters away from French territory on the left bank of the Rhine . According to the Final Act of the Congress of Vienna in 1815 , the Rhineland became a Prussian province . The fortification of the Koblenz area became a Prussian military priority , because of its proximity to France and the fact that Koblenz was a bottleneck for all means of transportation ( ships , railways , land transportation because of bridges ) . Hence , the Prussians built a system of fortification around Koblenz , the so - called Fortress Koblenz , from 1817 until 1834 . Yet , the name Fortress Koblenz should not be interpreted as if the whole city of Koblenz was a fortress . It should be rather viewed as a buzz word , referring to the ring of fortification around Koblenz , of which the Festung Ehrenbreitstein was a part . Fortress Koblenz was said to have been the largest military fortress in Europe except for Gibraltar . However , it is a common misconception , that the " Festung Ehrenbreitstein " alone was the largest fortress in Europe . Ehrenbreitstein could be defended by up to 1200 soldiers . Unchallenged , it remained in service until 1890 . In 1822 the English translation of the castle ' s name , " The Broad - Stone of Honour " , was used as the title of Kenelm Henry Digby ' s exhaustive work on chivalry . In 1897 , a Monument to Emperor Wilhelm I was erected right below the Festung , but on the west side of the Rhine , known as the " Deutsches Eck " ( German Corner ) . Both fortress and monument were considered as symbols for the " Guard at the Rhine " , as in the song " Die Wacht am Rhein " . During World War I the fortress was used as military headquarters . After World War I , the American General Henry Tureman Allen , convinced of its historical value as a premier 19th - century fortress , prevented its intended destruction . It was occupied by the US Army as their headquarters during the occupation of the Rhineland , and after January 1923 it was occupied by the French Army . During World War II , it served as a place of safekeeping for archives and cultural objects but also harbored three flak guns . After World War II , it was used first by the French Army before it was handed over to the State of Rhineland - Palatinate . It now has multiple uses including a youth hostel , restaurant , museum and archive . In 2011 , Festung Ehrenbreitstein will be part of the National Garden Show in Koblenz and is thus currently under renovation . Quote . " . . . this pulpit , I see , is a self - containing stronghold - - a lofty Ehrenbreitstein . . . " ( Herman Melville , " Moby - Dick " ) As the vine flourishes , and the grape empurples close up to the very walls and muzzles of cannoned Ehrenbreitstein ; so do the sweetest joys of life grow in the very jaws of its perils . ( Herman Melville , " " ) Here Ehrenbreitstein , with her shattered wall < br > Black with the miner ' s blast , upon her height < br > Yet shows of what she was , when shell and ball < br > Rebounding idly on her strength did light ; < br > A tower of victory ! from whence the flight < br > Of baffled foes was watch ' d along the plain : < br > But Peace destroy ' d what War could never blight , < br > And laid those proud roofs bare to Summer ' s rain - - < br > On which the iron shower for years had pour ' d in vain . < br >