The triapsidial church is said to have been founded in gratitude by Empress Theophanu, the Byzantine wife of Emperor Otto II. The visible remains of the original Romanesque building are the semi-circular apses with wall paintings from 1215. In the vaulting of the left apse the Virgin Mary can be seen with Jesus and two angels as well as episodes from the Life of St Margaret. In the main apse are the Pantocrator and the symbols of the Four Evangelists. Beneath the Five Wise and the Five Foolish Virgins are portrayed. The right apse shows St Margaret between two angels. Underneath are the Judgement, the Martyrdom and the Beheading of the saint. Bestiary figures are represented on the socles.