The ruins of Frohberg castle is on a rocky ridge at the upper end of the Klus valley on the way to the old Platten pass road. The stronghold at Frohberg was first mentioned in 1292 when Conrad I Schaler 'de Vroberg' was mentioned. It is likely that the castle was built by the Schaler family in the second half of the 13th Century. Although the castle dominated the way across the Platten pass (between Birseck and Laufental), the location of other castles in the immediate vicinity, suggests that the motivation for the castle was not the collection of tolls, but power games between the families of the Schaler and Münch.
The castle was perhaps never quite finished or it castle was damaged during the Basel earthquake of 1356 and was not repaired. In any case, in the 14th Century, the remains were given as a bishop's fief to the counts of Thierstein-Pfeffingen. This fief was not so much about the ruins, which needed costly repairs, but the assets related to the castle including tax collection and court rights.
The ruins are widely scattered and consists of an extended main castle, surrounded by different approach obstacles. So far, the ruins have not yet been investigated archaeologically and so only rough interpretations are possible. The main castle was formed by a housing tract and a curtain wall. The wall follows the irregularly extending ledge. The massive living area consists of two parts and a smaller west building with irregular floor plan as a residential tower. The thick walls were up to 3 meters thick and built from rough cut stone. To the east, adjoining the living area, is an elongated building that served as an administrative and residential building. On the northwest and northeast sides the remains of outlying estates are visible.
References:The Pilgrimage Church of Wies (Wieskirche) is an oval rococo church, designed in the late 1740s by Dominikus Zimmermann. It is located in the foothills of the Alps in the municipality of Steingaden.
The sanctuary of Wies is a pilgrimage church extraordinarily well-preserved in the beautiful setting of an Alpine valley, and is a perfect masterpiece of Rococo art and creative genius, as well as an exceptional testimony to a civilization that has disappeared.
The hamlet of Wies, in 1738, is said to have been the setting of a miracle in which tears were seen on a simple wooden figure of Christ mounted on a column that was no longer venerated by the Premonstratensian monks of the Abbey. A wooden chapel constructed in the fields housed the miraculous statue for some time. However, pilgrims from Germany, Austria, Bohemia, and even Italy became so numerous that the Abbot of the Premonstratensians of Steingaden decided to construct a splendid sanctuary.