The building belongs to the late work of the famous baroque architect Peter Thumb (1681 - 1766) from 1753 - 1755. The Gothic lower parts of the Tower remained unaffected. Stucco work from the Rococo period by Wessobrunn master Johann Georg Gigl as well als ceiling paintings by the Young Swabian Artist Eustachius Gabriel ornamented the building's appearance. In Addition, the chapel is lined with frescoes which represent the Assumption of Mary, the Transfiguration of christ and the town's two Patrons Sebastian and Agatha. Particularly striking is the variety of Emblems which adequately Combine quotes from ancient authors with biblical passages. Despite its plain facade, the impressive and harmonious building celebrates Baroque splendour and the architect's long experience once again. During the culture war (1874 - 1883), it served as an Old Catholic church.
