Underground cistern built between 1770 and 1772 based on a design by Neapolitan engineer Carlo Zoccoli, to replace the cistern of the Renaissance structure, on whose site was built the new Church of San Pancrazio (subsequently demolished), after the demolition of the ancient church, that belonged to the Basilian Monastery of San Pancrazio which stood in the center of the courtyard, commissioned by Fulco Antonio Ruffo.
At the end of the 18th century, restoration work was carried out on the castle's 16th-century structure.
The project, commissioned by the Ruffos to Neapolitan engineer Carlo Zoccali, “Master of fortifications more than many more experienced officers”, was overseen by his son Raffaello.