Koblenz was established as a Roman military post by Drusus c. The city celebrated its 2,th anniversary in The city ranks as the third-largest city by population in Rhineland-Palatinate , behind Mainz and Ludwigshafen am Rhein.
Its usual-residents' population is , as of [update]. Koblenz lies in a narrow flood plain between high hill ranges, some reaching mountainous height, and is served by an express rail and autobahn network. It is part of the populous Rhineland. Historic spellings include Covelenz , Coblenz , and Cobelenz. In local dialect the name is as the first historic spelling indicates, in German orthography, Latscho Kowelenz.
Around BC, early fortifications were erected on the Festung Ehrenbreitstein hill on the opposite side of the Rhine. Remains of a large bridge built in 49 AD by the Romans are still visible. The Romans built two forts as protection for the bridge, one in 9 AD and another in the 2nd century, the latter being destroyed by the Franks in North of Koblenz was a temple of Mercury and Rosmerta a Gallo-Roman deity , which remained in use up to the 5th century. With the fall of the Western Roman Empire , the city was conquered by the Franks and became a royal seat.
In , it was assigned to Charles the Bald , and a few years later it was here that Carolingian heirs discussed what was to become the Treaty of Verdun , by which the city became part of Lotharingia under Lothair I. At the first synod, held in the Liebfrauenkirche, the reconciliation of Louis the German with his half-brother Charles the Bald took place.
In , the city was given by the emperor Henry II to the archbishop-elector of Trier after receiving a charter. It remained in the possession of his successors until the end of the 18th century, [ 3 ] having been their main residence since the 17th century.
