It occupied the south-eastern side of the Forum (coming from the Byzantine Gate, on the right). Severely damaged by lightning at the end of the 3rd century AD, it was rebuilt during the Constantinian period (beginning of the 4th century AD) according to the same plan, with a rectangular layout surrounded on all four sides by a colonnade. The Corinthian columns of grey granite, two of which have been raised, belong to the Constantinian phase, whereas the columns of the previous basilica must have been of limestone.