Ruins of the castle
Rovine del castello
The castle (castellone
for local population) of Cervinara is mentioned in the first fact we know at all about the town — written in the 12th century, but referring to the year 837. Although subject to interpretation, this suggests that it was built around the 9th century by the Langobards; and this does not surprise considering how common were invasions at that time, and that Cervinara was about to become the boundary between the principalities of Benevento and Salerno. It may also be the case that it was built on the site of some Samnite fortifications.
In the following centuries, it was devastated repeatedly. Once was probably in the 1130s, when Roger II was fighting against the count Rainulf in Valle Caudina. At some point the castle was rebuilt, but destroyed again by the troops of king Frederick II fighting against the local feudatories in the 1220s; later on, in particular under the Angevins, it was employed again. Unfortunately, probably since the mid-15th century, the castle was progressively neglected by the feudatories. In 1528 it is mentioned as being "half ruined", and in 1562 the construction of the marquises' palace more downhill started. From that moment on, the castle was completely abandoned, and architectural elements stolen from it. The remains has been reinforced only recently.
The castle lies on top of a hill, naturally isolated by the ravines around it, on a roughly flat acreage. It is built in local lime stones, according to essentially Norman-style plan. The perimeter walls — only some portions of which are still standing — enclose a roughly rectangular yard, about 75 m long and 30 m wide. Seven small towers take places along the walls.
Within the walls, the most important remains are the ones on the northern side, and consist in the remains of a moderately big two-storey building with the castle's keep in the middle. Probably, according to a common arrangement, the ground floor was inhabited by the servants and the upper floor by the feudatories, so that they had direct access to the keep in case of attack. The keep itself is a locally rare example of tower preserving most of its original elevation. The opposite side of the castle yard may have hosted some service sheds.
Enzo Napolitano, I castelli della Valle Caudina, 1989
Part of the paragraph above is inspired by this book by an active local historian of the Middle Ages. In particular his book features a deep analysis of the structure of the castle.
Il castello di Cervinara [Avellino Turismo]
This shorter webpage about the castle is also a reasonably good source.