First built in the 5th century, St. Simeon's Church has undergone alterations until as recently as 1980, and some find the terracotta and white exterior disappointing in comparison with the other churches. This 17th-century church is best known as the home of the mummified body of St. Simeon, one of Zadar’s patron saints.
The Chest of Saint Simeon is a rectangular cedarwood sarcophagus in the shape of a chasse, overlaid with silver and silver-gilt plaques, said to hold the relics of St Simon the God-receiver; it is located over the main altar in the Church of Saint Simeon. The chest, considered a masterpiece of medieval art and also a unique monument of the goldsmith's craft of the age, is one of the most interesting works in gold in Europe now under the protection of UNESCO. It was made by local goldsmiths to an Italian design between 1377 and 1380.
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.