Description
The Golden Square had a large central garden surrounded by a portico and a series of rooms on the north, east and south sides.
The main access was to the north, with corridor PO1 and the octagonal Vestibule PO2 covered by an "umbrella" dome, typical of Hadrianic architecture.
Umbrella dome of the Vestibule
The Vestibule gave access to the northern corridor of the large quadriportico PO6, which surrounded the vast central uncovered area PO7 decorated with flowerbeds and long water basins.
Along the north side, on both sides of the Vestibule PO2 there are two exedras: PO3 with a beautiful polychrome mosaic, and PO4.
Below them, as a substructure, there was a Cryptorticus linked to the subterranan road network.
Parallel to the east and west sides of the PO6 portico are two outer corridors PO35 and PO8. The walls that separate them from the porch have a large number of rectangular niches.
The large Triclinium PO42
On the eastern side of Piazza d'Oro there is the large triclinium PO42 in front of which was the water basin PO41.Other rooms overlook the underlying Valley of Tempe, from which is visible a roadway [no. 8b], partly subterranean, that goes towards the Great Trapezium.
The south side of Piazza d'Oro has a series of curvilinear rooms that pivot around the main quatrefoil hall PO20, the most important and monumental one of the building.
On one side is the large PO23 exedra, which was the scenographic end of the complex. It had seven alternating semicircular and rectangular niches, placed on a podium and framed by columns and small pediments of precious marbles.
From the niches jets of water flowed down and vere collected by a water basin below; then the water flowed into the long basins of the central courtyard.
At the four corners of hall PO20 there are four fountains PO21, 22, 24 and 25, and inside the masonry of their pillars four small single latrines have been built.
To the east and west of hall PO20 there are two groups of symmetrical rooms, that have very high walls and open onto two central courtyards, PO17 and PO28.
Opus sectile restored pavement
All the rooms had opus sectile pavements made with precious marbles; unfortunately only the imprints of the marble slabs remain in place. In one corner of portico PO6 a parte of the opus sectile pavement was restored. The two exedras PO3 and PO4 had a mosaic pavement with squares of different colors.
On the walls there are the traces of the nails used to fix the marble revetment, which reached up to the ceiling.
In rooms PO29 and PO31, the fragments of a magnificent marble frieze with hunting scenes are kept since decades under precarious canopies. It would be advisable to display them in the Antiquarium of the Villa.
Frieze with hunting scenes
Finally, at the north-east corner of the portico, in room PO5, a staircase descended to a group of rooms PO45-55,which is not open to the public any more. One of them had a magnificent opus sectile pavement made with alabaster, that was covered and is not visible any more [ PHOTO alabaster].
Those rooms were the access to the Golden Square for those arriving from the Terrace of the Golden Square,along the route coming from the Fede Nymphaeum, which was several meters lower than the rest of the building.
The name Golden Square obviously alludes to the treasures that were found there; Ligorio speaks of the discovery of statues of Nymphs of the Ocean, of an Egyptian Venus and of Hipponoe.
The eighteenth-century excavations of count Centini (heir of Count Fede and owner of the area at that time) stripped the building of its marbles; some capitals were sold to the Vatican Museums and today decorate the Sala delle Muse (see De Franceschini Marmora).
The building was excavated several times. In 1883 Lanciani found a head of Marcus Aurelius; in 1958 a loricate bust of Caracalla was found. Both prove that the Villa was used and visited by other emperors after Hadrian [PHOTO sculptures?].
Only the Vestibule, the Triclinium PO42 and other rooms along the portico are open to the public. On the south side, hall PO20 and surrounding rooms are closed and so are the exedras on the north side.
Function and meaning
The Golden Square had opus sectile pavements, of which only a few fragments remain restored in situ. The walls were all revetted with precious marbles and there were individual latrines. This proves that it belonged to the imperial and noble quarters of the Villa.
There is not enough evidence to understand it function. Some hints can come from the comparison with a building that has a very similar plan: the Stoà of Hadrian in Athens.
It was a monumental library built by the emperor in those same years, and had a large central exedra with niches for statues flanked by large rooms.
Perhaps the Golden Square was the great Library of the Villa, worthy of a cultured emperor like Hadrian.
In particular, the numerous niches visible in the side corridors PO8 and PO35 could have been used to house the papyri of a large library.
SEE: Marina De Franceschini, Villa Adriana. Mosaici, pavimenti, edifici, 1991, Piazza d'Oro, pp. 147-159 e 463-477.
About the Golden Square as a possible Library of the Villa: pp. 469-478.