Cathedral and, like the Frauenkirche at Munich, have copper "onion towers", which were added after a fire in 1561. Between 1657 and 1670 the church was extended by the construction of a sacristy in the Lady Chapel, an oratory and a crypt beneath the chapel of Saint Barbara. Until the secularisation of Bavaria in 1803 Seeon was a place of learning and culture: Joseph Haydn was a guest here, and Mozart was active here between 1767 and 1769. After 1803 the abbey was dissolved and the buildings were turned into a castle, and used later at various times as a medicinal spa, convalescent home and barracks. The infirmary and the library were demolished, and a causeway constructed connecting the island to the mainland. In 1989 the premises were eventually acquired by the government of the administrative region of Oberbayern and after a lengthy restoration reopened in 1993 as a cultural and educational centre, which is now used for concerts, exhibitions, seminars, conferences and workshops. Since 2017, the Christian Social Union's group in the German Parliament has been holding its annual retreat at Seeon Abbey. Notable guests at the retreat have since included Prime Minister Erna Solberg of Norway (2017); European Commissioner Julian King (2017); Mayor of Kyiv Vitali Klitschko (2018); Prime Minister Leo Varadkar of Ireland (2019); and President Klaus Iohannis of Romania (2020). Burials Frederick II, Count of Diessen Engelbert, Duke of Carinthia Anna Anderson Note Encomium by Gerhard of Seeon on Emperor Henry II and his foundation at Bamberg References External links 10th-century establishments in Germany Christian monasteries established in the 10th century 11th-century churches in Germany Monasteries in Bavaria Benedictine monasteries in Germany 994 establishments Traunstein (district)