Spangenberg Castle is the partially rebuilt ruin of a rock castle in the German state of Rhineland-Palatinate. It lies in the Palatine Forest above the Elmstein valley near the village of Erfenstein, but is actually on the forest estates belong to the town of Neustadt an der Weinstraße, or more precisely, the village of Lachen-Speyerdorf. Together with the neighbouring castle of Erfenstein, it is linked to the legend of the Leather Bridge.

A rock castle is a type of medieval castle that directly incorporates natural rock outcrops into its defences to such an extent that the rock formations define the structure of the castle. Topographically, rock castles are classified as hill castles.