was then reduced to the height of the first floor together with its link to the east wing. The remaining, initially single-storey stump of the bergfried is recorded in a pen-and-ink drawing made during the Thirty Years' War. Later it continued to decay. The remaining wall stones of the tower were rebuilt to a height of about a metre during its renovation in the 1960s. A roughly metre-high shaft in the courtyard, below the eaves between the south and west wings serves to collect rainwater and feed it into the cistern which is formed by a large cavern in the castle rock. The 1807 construction survey report mentions that this cistern was still important as a supply of drinking water around 1800. When the castle fell into ruins in the first half of the 19th century, the cistern became filled with rubble which has still not been cleared out. History Archaeology and architectural research Nothing is known about any settlement on the castle rock in pre-mediaeval times. During the renovation of the castle at the end of the 1960s, a late Ottonian disc fibula made of bronze was discovered; its style dating to the end of the 10th century or first quarter of the 11th century. There is a high probability that it originated from the workshop of Egbert of Trier. Because the ornamentation of fibulas soon fell out of fashion with the advent of the Salian dynasty, it was probably lost on the plateau of the zwinger prior to 1030. The brooch is displayed today in the Franconian Switzerland Museum in Tüchersfeld and is the oldest find from the castle hill. Although it is plausible that the castle rock was thus used as early as the early 11th century, no predecessor structures or remains of last Ottonian or Salian foundation walls have been found. What is certain is that the earliest record of the fortress occurred during the Hohenstaufen era, in an 1139 deed. Architectural and radiometric investigations of the foundation walls have not been carried out in sufficient detail to be able to date the castle more precisely than the sparse written records have indicated. Thousands of pieces of pottery, uncovered during the renovation of the castle in the 1960s in the courtyard and in the ground layers of the zwinger, date mainly to the Late Middle Ages (c. 1250 to 1500); older shards of pottery are the