In the 11th century Archbishop Pilgrim had a canons' monastery built on the site of today's Church of St. Apostles, which was remodelled in the following century. Inside, both construction phases are successfully combined. Around 1200 St. Apostles received a richly structured cloverleaf choir and an octagonal dome above the crossing, which appears almost Byzantine. The new spatial effect is particularly impressive due to the modern painting of the choir complex by Hermann Gottfried.