Since 1989 the Soprintendenza per i Beni Archeologici del Lazio has advanced the excavational and restorational campaigns still in progress, on the sanctuary of Diana Aricina. The sanctuary stands on the northern bank of Lake Nemi, on the Alban hills. The cult was born at the end of the 6th century BC, when, according to the testimony of the ancient authors Cato and Festus, a wood was dedicated to Diana in her triple aspects of goddess of the hunt, of the nocturnal light, and of birth. The sanctuary was a federal institution, the seat of the Latin League which dissolved in 338 BC. Some terracottas represent the original form of the temple, which dates back to the 4th century BC and belonged to the Etrusco-Italic type, with wooden structure, dressed in terracotta, open pediment, four columns on the front and spacious cella with side wings. At the end of the 2nd century BC the sanctuary undergo a consistent monumentalization assuming the appearance of other large and contemporary Latin sanctuaries. The new complex is organized on a large platform sustained by substructures, upon which rise chapels for the divinity, rooms for pilgrims and the priests, and a building conventionally considered the temple of Diana. Other scholars, however, believe that the main temple was situated on the upper terrace. In the course of the 1st century BC a large part of the colonnade which was found on the platform is enclosed to form rooms with the probable function of "treasure cellas," so interpreted for the quantity of statues and ex-votos that were found there. Contemporaneously, a theater and bathing installation is constructed. New restorations are undertaken by representatives of the Julio-Claudian family and by the emperor Hadrian. With the advent of Christianity the sanctuary is abandoned and progressively plundered of all of its furnishings.

In 2003, the Soprintendenza per i Beni Archeologici of Lazio appointed S. Piro of ITABC-CNR to undertake a georadar survey on the terracing situated east of, and 30m lower than the terrace on which the well known sanctuary stands. The structures recorded by the survey were excavated in the same year. These comprise an imposing, semicircular nymphaeum, probably built in the early Imperial period, overlying an open-air cistern of late Republican date. In front of the nymphaeum, beyond an open space delimited by lateral terrace walls, were the remains of what was probably a blocked doorway and a small side room with an opus spicatum pavement. This area terminated with a longitudinal terrace wall in opus reticulatum behind which was a terrace wall from an earlier phase, in opus quasi reticulatum, and on a slightly different alignment to the other structures. The last phase of terracing formed the back wall to a series of small rooms. In 2004 a terrace came to light in the area immediately below on which stood four rooms belonging to various building phases. Of these, room 1 must have had a series of tile built columns, and its west wall contained at least two semicircular niches: room 2 produced numerous fragments of painted wall plaster and black and white mosaic tesserae. Excavations were then undertaken in the area immediately above the sanctuary's vast middle terrace, which revealed what was probably a passageway, connecting this terrace to those above, the west side of which is faced with opus reticulatum. On the south side of the structure were several slabs of tufa with channels cut into them. (Giuseppina Ghini - Francesca Diosono)