The corridor’s mosaics (4th and 5th c. A.D.) were the most important and complete examples of the artistic perception that characterizes the decoration of the complex. Thematic and chromatic variations unfold harmoniously like polychrome tapestries. Their geometric compositions cover large surfaces, being either repeated or in the form of continuous panels enclosing various motifs.
The central building complex underwent many alterations and repairs, noted particularly in the masonry surrounding the corridors, making it difficult to restore its original form. Due to wear and tear on the mosaic floor, in the 5th century A.D. a new floor was built between the marble stairway and northwestern gate. It featured a central zone of marble slabs framed by a coarse mosaic (opus segmentatum) of irregularly-shaped colored marble tiles.
Central building complex. Plan of the second building phase with graphic reconstruction of floors.