[16][12][17] When a young Roman inadvertently fell through a cleft in the Esquiline hillside at the end of the 15th century, he found himself in a strange cave or grotto filled with painted figures.

[18] The Fourth Style frescoes that were uncovered then have faded now, but the effect of these freshly rediscovered grotesque[19] decorations (Italian: grotteschi) was electrifying in the early Renaissance, which was just arriving in Rome.

[20] Beside the graffiti signatures of later tourists like Casanova and the Marquis de Sade scratched into a fresco inches apart,[21][verification needed][22] are the autographs of Domenico Ghirlandaio, Martin van Heemskerck, and Filippino Lippi.

[24] The frescoes' effect on Renaissance artists was instant and profound (it can be seen most obviously in Raphael's decoration for the loggias in the Vatican), and the white walls, delicate swags, and bands of frieze—framed reserves containing figures or landscapes—have returned at intervals ever since, notably in late 18th century Neoclassicism,[25] making Famulus one of the most influential painters in the history of art.

[30] Suetonius claims this of Nero and the Domus Aurea: When the edifice was finished in this style and he dedicated it, he deigned to say nothing more in the way of approval than that he had at last begun to live like a human being.

[31]The Domus Aurea complex covered parts of the slopes of the Palatine, Oppian, and Caelian hills,[27] with an artificial lake in the marshy valley.

[33] Suetonius describes the complex as "ruinously prodigal" as it included groves of trees, pastures with flocks, vineyards, and an artificial lake—rus in urbe, "countryside in the city".

[36] To supply his lake in the valley between the Palatine, Oppian, and Caelian, Nero diverted water from the Aqua Claudia by a specially built branch aqueduct known as the Arcus Neroniani.

[41] The statue was placed just outside the main palace entrance at the terminus of the Via Appia[31] in a large atrium of porticoes that divided the city from the private villa.

[11] Rooms sheathed in dazzling polished white marble with paintings above had richly varied floor plans, complete with niches and exedras that concentrated or dispersed the daylight.

The building plan is divided into two parts: the western one is simple and classic in design, characterised by perpendicular axes and built around a large rectangular courtyard, which opened towards the valley and the lake.

The eastern part is of a much richer design[51][52] with two of the principal dining rooms flanking an octagonal court, surmounted by a dome with a giant central oculus to let in light.

It was built on the model of the cenatio praecipua rotunda (dining room whose ceiling constantly revolved like the heavens) which Carandini and Fraioli position in the pavilion.

The ceiling of the octagonal hall could probably rotate by means of a mechanism created by Celer and Severus and similar to a millstone which, hooked to the uncovered tracks along the edge of the central opening, was moved by slaves.

According to some accounts, perhaps embellished by Nero's political enemies, on one occasion such quantities of rose petals were dropped that one unlucky guest was asphyxiated (a similar story is told of the emperor Elagabalus).

[57] One innovation was destined to have an enormous influence on the art of the future: Nero placed mosaics, previously restricted to floors and gardens, in the vaulted ceilings.

Only fragments have survived,[58] but that technique was to be copied extensively, eventually ending up as a fundamental feature of Christian art: the apse mosaics that decorate so many churches in Rome, Ravenna, Sicily, and Constantinople.