Adenau () is a town in the High Eifel in Germany. It is known as the Johanniterstadt because the Order of Saint John was based there in the Middle Ages. The town's coat of arms combines the black cross of the Electorate of Cologne with the lion of the lords of Nürburg. The northern loop of the Nürburgring lies just outside the town. The Breidscheid section of Adenau was a separate municipality until 1952. The lords of Breidscheid are mentioned in the 13th Century. The chapel of Breidscheid is dedicated to Saints Roch and Sebastian and was built in 1630 as a plague chapel.