Four medieval buildings (13th-14th century) were found in the “Duomo” station at piazza Nicola Amore (also known as dei Quattro Palazzi), which was opened during the “Reclamation”. These structures show a change in use of the area, with the obliteration of the defensive walls which, from the Greek period (5th-4th century B.C.) until the ducal period (11th century A.D.), had characterised the topography of this zone, situated along the northern side of the present piazza, at the crossroads with via Duomo.

Of the Greek walls two tufa tie courses were preserved, belonging to the 5th-4th century B.C. phase which, facing the sea, starting from the projecting hill of San Marcellino, formed an ample indentation as far as piazza Nicola Amore. The wall then continued below Corso Umberto I towards via P. Colletta and piazza Calenda. The internal curtain wall was preserved, reused in a medieval sewer, whilst the external curtain was robbed in the same period. However, the negative traces of the removed tufa blocks remained impressed on the cement core of an imposing scarp of quadrangular tufa ashlar, preserved to a height of over 5 m. Reinforced with opus caementicium cross walls, it was probably built during the work to restore and enlarge the town walls undertaken by Valentinian III in the 5th century A.D. or was part of the restorations undertaken by Narsete in the 6th century A.D. during the Graeco-Gothic war.