The first true knowledge about the foundation of the St. Vitus abbey dates back to a document from the late 11th century, probably from the scriptorium of the monastery of Gladbach. This richly illuminated document reports that a nobleman long before the founding of the abbey would have erected a church on the top of the hill, a church destroyed by the Magyars in 954.
In 1120, at the latest, the monastery was affected by the Benedictine reform Siegburg. The nave of the abbey got its definitive form between 1228 and 1239. Between 1256 and 1277, while reconstruction was developing, the idea of building a new choir appeared, but on a different plane (the typical elongated choir of the Gothic style). In order to carry out this plan, Master Gerhard, the first architect of Cologne Cathedral brought to his experience. Albert the Great consecrated the abbey on April 28, 1275.
The old Benedictine monastery church was elevated in 1973 to the rank of Minor Basilica by Pope Paul VI.
References:The Château du Haut-Koenigsbourg is situated in a strategic area on a rocky spur overlooking the Upper Rhine Plain, it was used by successive powers from the Middle Ages until the Thirty Years' War when it was abandoned. From 1900 to 1908 it was rebuilt at the behest of the German kaiser Wilhelm II. Today it is a major tourist site, attracting more than 500,000 visitors a year.
The first records of a castle built by the Hohenstaufens date back to 1147. The fortress changed its name to Koenigsburg (royal castle) around 1157. The castle was handed over to the Tiersteins by the Habsburgs following its destruction in 1462. They rebuilt and enlarged it, installing a defensive system designed to withstand artillery fire.
The fortification work accomplished over the 15th century did not suffice to keep the Swedish artillery at bay during the Thirty Years War, and the defences were overrun.