The small Antiquarium of Casteltermini, in addition to a large section dedicated to archaeology, presents in the first room a selection of works by Michele Caltagirone, known as Quarantino, by the historian Gaetano Di Giovanni, and by the illustrious pedagogue Giovanni Agostino De Cosmi. Rooms 2 and 3 display a selection of artefacts acquired during excavations and surface reconnaissance in the area. The oldest testimonies are those found on Monte Roveto and refer to the ancient Neolithic period. From the northern slopes of Rocca Grande di Roveto come valuable ceramics ascribable to the S. Cono-Piano Notaro style (Ancient Eneolithic), and ochre-banded painted ceramics of the Serraferlicchio style. The final phase of the Eneolithic is also well attested, with ceramics of the Malpasso style, with a red monochrome surface, and of the Ancient Bronze Age (end of the 3rd millennium 16th century B.C.), with ceramics ascribable to the Naro and Castelluccio cultures.
Brief excavation campaigns on Monte Roveto and in contrada Sanfilippo date back to 1995 and 1998. Here, an architectural complex of sacred rooms and precincts was brought to light, in which dozens of votive offerings dating from the 6th century B.C. were found, consisting of indigenous, imported Greek and locally imitated vessels. The vessels were placed in ditches dug in the earth, sometimes surrounded by a circle of stones, standing upright or upside down, often close to walls. Of great importance is the series of hut models, miniature shields, the cassetta-larnax, rare types of objects used in the sacred sphere. Room 3 displays some of the most representative finds from the area, the result of surface reconnaissance. An exception is the site of Santa Croce-Fontana di Paolo, where in 2006 three large cisterns full of material from the 6th-5th century BC, tiles and various pottery were excavated.
The Attic pottery dating from the 5th century BC is of exceptional quality. Due to the need for space, only a few sites in the area are represented, such as contrada Fabbrica-Santa Maria, where the remains of a dolmen monument and a large lithic platform with communicating basins have been identified, an element that is always found in connection with dolmen-type structures. In contrada Serre, there are exhibits from the late Antiquity period, some of which have a precise Christian character, such as a bronze ring with an engraved monogram, clay hands, including one blessing, and bronze coins.