The excellent preservation of structures and materials of the Ibero-Roman stage of Libisosa is due to the "burial effect" caused by its hasty and systematic destruction, which has allowed a frozen image of its state prior to the devastation to reach the present day,[1][2] which constitutes a mine for research on the Final Iberian and Republican Hispania, most of which has yet to be discovered.

And if this phase is important it is due to its exceptional state of preservation, motivated by a sudden destruction, which has been related to the Sertorian wars (82-72 BC),[8] and which offers an unaltered image of the moment immediately prior to that devastation, both in terms of structures and materials.

[28] After a period of difficult archaeological localization, the ancient Oretan oppidum will experience a definitive promotional leap, with its conversion into the colonia Libisosa Foroaugustana, to which Rome granted, as it is clear from the reading of Pliny the Elder (HN, III, 25), the ius italicum, the highest legal consideration, perhaps as a reward for fixing the population in this strategic area.

As regards the material record, archaeological excavations have recovered from the forum a large ceramic collection, but also some fragments of inscriptions,[29][34] testifying to the existence of IIviri, and reiterating the belonging of the colony to the Galeria tribe; three Corinthian type capitals, various sculptural[35] remains of togados, and portraits of Julio-Claudian characters (one of them with damnatio memoriae), coins (denarii and Republican and Imperial aces), an altar pulvinus, decorated with a rosette of five petals, etc.

[29] To these new materials provided by recent excavations it is necessary to add the ancient findings, such as the small head, preserved in the Museum of Albacete, belonging to a lady of the Libyan elite that follows the reference of the empress Iulia Agrippina Minor.

However, the northern part of the forum shows signs of destruction (probably related to natural causes, such as landslides or seismic movements) and its subsequent remodeling, with the restructuring of the portico and the inclusion, at least, of a kind of monumental fountain,[37] as well as the raising of the paving levels of the forensic square.

During the reign of the Catholic Monarchs and throughout the 16th century, the town grew due to the granting of the status of villa to Lezuza, but the Cerro del Castillo was abandoned as a place of habitat, and the settlement was established on the plain, around the new church.