Along the footpath leading up from the park the visitor passes the ruins of the gatekeeper’s house and the “Castle Stein”. This former property of the “Herren von Stein” was first mentioned in the 14th century. It survived the havoc of the 30-Years-War and was still inhabited until the late 18th century. Passing another medieval ruin and the adjacent falconry you come to the heart of the castle complex. At the entrance to the exterior courtyard, with a view over the Rhine valley, you find the foundations of the former chapel. This double-chapel was discovered during the restoration works in 1984 and boasts a precious ornate floor mosaic dating back to the early 13th century. In front of the chapel lies a well. During the restoration works it was excavated to a depth of 25 m, without, however, having reached the bottom. At a depth of 17 meters a hollow measuring some 20 square meters was discovered – unfortunately without the hoped for treasures. Passing through the large wooden gate, guarded by a stone relief of the Lion of Sayn, you reach the interior courtyard. The mostly restored castle keep with its mighty walls (2.40 meters thick and 20 meters high) dates back to the late 12th century. At the northern end of the courtyard lies the castle restaurant DIESAYN BURG. The name originates from a gothic relief of the saint which was found here during the excavations. The restaurant serves as an event location, either in the cozy atmosphere of the tavern or on the terrace with ist impressive panoramic view.