[8] The entrance from the coast on the south-west side gave a monumental view of the facade with two polygonal towers with several floors jutting out towards the sea and behind which was the residential area (D), while to the left was the large porticoed peristyle (A), the public part, with a double row of columns.
The walls of the portico were painted red, at least in the lower part and facing its entrance from the beach on the opposite side of the quadriportico was an arch between the columns.
The private, residential part had rooms around a small colonnaded atrium (D1) and was raised on the dunes, on a platform enlarged by a cryptoporticus so as to give a panoramic view over the sea.
The original northern entrance in room B was moved to the west and the atrium B was converted into a kitchen and paved with a patchwork of mosaic fragments from the previous phase.
[9] From the middle of the 1st century (3rd phase), a group of two-storey modular housing units (F) in opus reticulatum were built along the northern border of the complex, probably intended for slave labour (ergastulum).
From about 130 AD in the Antonine era (phase 5) there was a major restructuring of the peristyle area, with the insertion of baths in the western corner, equipped with heated rooms and pools.
After about a century, excavations resumed at the suggestion of the archaeologist Carlo Fea, who managed to convince Prince Agostino Chigi to sponsor the initiative.
These last two campaigns revealed that the original interpretation was wrong; according to the archaeologist Colini, the Pliny the Younger's villa should in fact be in the presidential estate of Castelporziano.
In phase 5 the curvilinear design brick fountain was added, still visible today in the centre of the garden, and the row of internal columns was equipped with a small masonry balustrade.
The scene, which unfolds around the centrally positioned god, features: two announcers, a female with a sistrum (an ancient instrument of Egyptian origin) and another male with a flute; a female figure with a fish tail who holds in her hands a thyrsus (a long stick with a pine cone at the end) and various marine animals, including seahorses, a sea lion, a lobster, a shrimp, some fish and a dolphin.
The paleo-Christian basilica, measuring 16.6 x 9.4 m, which stands outside the northeast supporting wall of the Villa della Palombara, a few steps from the ancient route of the Via Severiana, was discovered "by chance" in 1939 by Colini.