The castle ruin Rudelsburg lies on the east bank of the river Saale atop a rocky shell limestone ridge, approximately 85 metres (279 ft) above the river and above Saaleck, a suburb of the town of Bad Kösen in the Burgenlandkreis district in Saxony-Anhalt, Germany. The Rudelsburg was built in the Middle Ages by the Bishop of Naumburg and served to secure trade routes such as the Via Regia through the Saale Valley.