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The mighty medieval high altar, which was dedicated to St Peter the Apostle on 27 September 1322, stands at the centre of the chevet. The masonry altar is encased in black marble. The altar top (mensa) comprises a single slab of marble, the largest single stone in the entire cathedral. The four vertical surfaces of the altar are decorated by delicate arcades of white Carrarra marble, which stand out most effectively against the black marble background. Under the arches stand small white marble statuettes and, at the centre of each side of the altar, a small group of statues. The individual statuettes represent prophets, apostles, and saints, while the groups depict scenes from the life of the Virgin.
Dr. Klaus Hardering, Kunsthistoriker