History tells us that on February 13, 1503, at dawn’s first light, the thirteen Italians went to the Cathedral where, in the hands of Prospero Colonna, before the Sacrament, they swore to win or die.
Clearly visible on the right side of the Duomo is an inscription that was placed there, in memory of the event, on the 400th anniversary of the Challenge:

"Del gran capitaneo in Barletta nell'anno del Signore 1503 fu la gran vittoria et proprie in anno sexte indictionis".

Additionally, conserved in its interior is the effigy of the Madonna of the Challenge, painted in 1387 by Paulus Serafini de’ Serafinis and originally dedicated to Our Lady of the Assumption.

Used in Dauno-Roman times as a burial place, the area of the present cathedral was used in late antiquity for the construction of a large paleochristian basilica dating from Sixth Century AD. The present cathedral was built on top that church. It is composed of two parts which are architecturally and stylistically distinct, but admirably fused.

Its construction began in the first half of the Twelfth Century. The smooth columns are an ancient style with capitals of diverse forms and styles, some ancient and some contemporary to its construction. The inner loggia characteristic of the paleochristian style has been replaced on the upper walls of the nave with large mullioned windows.

In the first half of the Fourteenth Century, the second part was added where the bishop's throne, pulpit and three altars from the destroyed Cathedral of Canne are installed. Here the style is clearly Gothic. The three naves continue on in a Roman style but rest on square pillars with cross-vaulted ceilings in the central nave and barrel-vaults in the side naves. The side naves are quite a bit higher than Roman ones.

In this area, the church "widens" finally taking on a trapezoidal shape, invisible to the eye. The Gothic choir with which the building terminates, is made up of a large five-sided polygonal apse. The division of the deambulatory in chapels is also marked on the outside.

The sculpture in the church is datable to the middle of the Twelfth Century and is thus contemporary with its construction. The bell tower which rises on the north side, has four levels above the groundfloor arch, which today serves as the gateway to the historic center.