In 955 Emperor Otto I granted his estates in Zizers to the Bishop of Chur. Friedau Castle may have been built on the site of one of the buildings from this 10th century grant. Construction on the castle begun under Bishop Volkart von Neuenburg (1237-1251) but was completed under Heinrich IV von Montfort (1251-1272). Once it was completed it became the administrative center of the Herrschaft and the home of the bishop's landvogt.
Because the bishop often needed loans and donations, he used the castle as collateral for loans or as a reward for donations. In 1358 it was given as collateral to Beringers von Landenberg and four years later, in 1362, Bishop Peter Gelyto gave it to Kunigunde von Toggenburg. The Toggenburgs held the castle until the death of Frederick VII in 1436 and the extinction of the Toggenburg family. It appears that the castle had already fallen into ruin by 1387 and the bishop was just granting the rights to the lands and taxes associated with the castle. With those rights, the bishop included a clause that if the castle was rebuilt, the lands would return to him.
The castle must have been rebuilt sometime after the extinction of the Toggenburgs, because in 1503 there was once again a vogt at Friedau. In 1550 the chronicler Ulrich Campell recorded that the castle was a tower surrounded by a wall and moat. In 1649 the bishop sold the castle to the Vier Dörfer. From then on the castle was used as a prison and gradually became known as the Schelmenturm. In 1880 the tower was heavily damaged in a fire which destroyed much of Zizers. The heat was so intense that the stones in the wall cracked and two large rents opened up in the tower.
During an archeological excavation of the tower in 2016 several finger and foot bones as well as a leg bone were discovered. Initial speculation was that the bones came from tortured prisoners. However, Carbon-14 dating found that the bones dated from before the tower was built in the 13th century.
The castle is located in the center of Zizers. It is a square tower about 11.5 by 11.5 meters and has walls that are up to 2.3 m thick. It was originally four stories tall with a high entrance on the second story east side. Following the 1880 fire two large cracks have opened up in the walls.References:
Hluboká Castle (Schloss Frauenberg) is considered one of the most beautiful castles in the Czech Republic. In the second half of the 13th century, a Gothic castle was built at the site. During its history, the castle was rebuilt several times. It was first expanded during the Renaissance period, then rebuilt into a Baroque castle at the order of Adam Franz von Schwarzenberg in the beginning of the 18th century. It reached its current appearance during the 19th century, when Johann Adolf II von Schwarzenberg ordered the reconstruction of the castle in the romantic style of England's Windsor Castle.
The Schwarzenbergs lived in Hluboká until the end of 1939, when the last owner (Adolph Schwarzenberg) emigrated overseas to escape from the Nazis. The Schwarzenbergs lost all of their Czech property through a special legislative Act, the Lex Schwarzenberg, in 1947.
The original royal castle of Přemysl Otakar II from the second half of the 13th century was rebuilt at the end of the 16th century by the Lords of Hradec. It received its present appearance under Count Jan Adam of Schwarzenberg. According to the English Windsor example, architects Franz Beer and F. Deworetzky built a Romantic Neo-Gothic chateau, surrounded by a 1.9 square kilometres English park here in the years 1841 to 1871. In 1940, the castle was seized from the last owner, Adolph Schwarzenberg by the Gestapo and confiscated by the government of Czechoslovakia after the end of World War II. The castle is open to public. There is a winter garden and riding-hall where the Southern Bohemian gallery exhibitions have been housed since 1956.