The historical sources report that in the XII and XIII centuries, the fortified town of Civitella, built in order to control the surrounding valleys, was already a strategic point for the border of the reign. The town-walls were probably enlarged by Alfonse of Aragon at the end of the fifteenth century and at the beginning of the sixteenth Bernardo Buontalenti, in order to adapt the fortress to the changed defensive needs, added to its structure five circular ramparts and a pentagonal one. The real fortress on the top of the mountain extends for more than five hundred meters on the rocky ridge and covers a surface of 25,000 square meters. The present structure, restored in the Seventies of the last century, was built by order of the king of Spain Philip II of Habsburg in the second half of the sixteenth century and replaced the previous fort. The nineteenth-century tactical adjustments made the fortress strong enough to be the last bulwark against the Piedmontese siege in 1860-61. In 1988 the Museum of the Fortress was founded and situated in a few rooms of the building, which had previously functioned as an artillery depot. It exhibits a collections of arms and cannons dating from the Renaissance to the two big battles of the nineteenth century, in 1806 and 1860.