Ossiach Abbey - a former Benedictine monastery in Carinthia. Ossiach was founded by Otto III and is considered the oldest abbey Carinthia.

According to legend, the Polish King Boleslaw II the Bold was expelled in 1079 for the murder of St. Stanislaus and fled to Hungary and then wandered around Europe and found peace at last, when he arrived in Ossiach. There the king lived in a monastery as dumb repented for eight years, humbly performed the most complex works, is not on his deathbed told his confessor, who he was and what he did for repentance. The inscription on his tomb, located on the north side of the church building, says: "Boleslav, king of Poland, the murderer of St. Stanislaus, Bishop of Krakow."

The very Romanesque church was first mentioned in 1215. Restored in the late Gothic style after a fire in 1484.

When Abbot Werner (1307-1314) in Ossiach began centuries-old tradition of miraculous healings. Legend has it that Werner got three crystal sphere from the Mother of God for the healing of the blind, deaf and dumb. Up to now it remained only the smallest of the three areas that are stored in the Diocesan Museum in Klagenfurt.

In 1484 the monastery and church were almost totally destroyed by fire. Abbot Leonard Zorn resigned in the same year, and his successor, Daniel Berger Barney (1484-1496) began to rebuild the abbey.

Ossiach Abbey was dissolved in 1783 during the reign of Joseph II, after which the buildings were used as barracks. The library was destroyed and most of the books were transferred to the University of Graz. The church became a parish.

In 1816 the premises were largely destroyed. Between 1872 and 1915 the few remaining buildings have been re-used as a barracks and as a stable. Since 1995, the premises were handed over to the administration of Carinthia. Today it hosts the annual music festival.