Wulp Castle was built during the high Middle Ages. Despite this, the castle is documented only in a few found texts, and much of the castle's history is not known. However, in the chronicle of Muri Abbey, a castle that could perhaps fit Ruine Wulp's description - a castle in proximity to Zurich and Lake Zurich - was mentioned, but this has not been confirmed by other findings and is mere speculation. Also, a person named Eghart of Küsnacht was mentioned in the chronicle and several other documents to be the owner of the castle in the late 11th century. The castle was probably destroyed or abandoned already in the 13th century.
While no cemented and sure truth about the castle can be confirmed, progress has been made, including the finding of Bronze Age remnants after the excavation of the castle site, such as palisades. Other items have been uncovered about the castle's past, such as the altering of the castle in the 13th century, when it is presumed that most or all of the castle was replaced with a single tower and a central building, with only sections of the main wall still existing. After an unknown period of time, the Barons von Regensbergare known to have assumed ownership of Ruine Wulp, and also are known to have made plans to completely renovate the castle, but the plans probably were never realised.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.