Domus Aurea

Following the reign of Augustus came a succession of four emperors descending from the Julio-Claudian line: Tiberius, Caligula, Claudius and Nero. Each of these emperors tried to imitate the popular qualities of Augustus while also carving out a niche of originality and innovation. This tendency was reflected in legislation, imperial endeavors, and, key to our focus, in building programs.
There was no more visible way for an emperor to publicize his strength and good will to the Roman people than by erecting impressive buildings that glorified himself and improved the quality of Romans' lives. Emperors typically sponsored the building of new aqueducts, temples, markets, theaters, granaries, and fora. They also built lavish palaces for their own living quarters and employed the most distinguished architects and artists in all the Roman Empire.
One palace that caught the eyes of all was the Domus Aurea, called the Golden House according to some ancient writers because parts were overlaid in gold leaf and embedded with gems and rare seashells. Construction was started on Nero's new palace after the great fire of Rome. Some say he allowed the fire to spread so he would have the land for this magnificent structure. The story is unsubstantiated but we do know that so many buildings burned that a large parcel of land was cleared. Nero's first home, the Domus Transitora, was one of those destroyed. This house was certainly no humble abode. As its name implies, it created a passage between the Palatine and Esquiline Hills.
But now Nero had an excuse to build a newer and grander structure. He began his new palace immediately and continued to enhance it until his death four years later in 68 A.D. It too spanned the Esquiline and Palatine Hills but also occupied most of the Caelian Hill as well. It even replaced the Temple of Claudius the God, which Nero demolished.
Unfortunately, very little of the Domus Aurea exists today because later emperors replaced parts of the structure with their own buildings. However, comments from ancient historians and archaeological evidence allow us to visualize the palace.
Severus and Celer, the best architects of the day, designed the complex, which was described by Suetonius:

A huge statue of Nero, 120 feet high, stood in the entrance hall; and the pillared arcade ran for a whole mile. An enormous pool, more like a sea than a pool, was surrounded by buildings made to resemble cities and by a landscape garden consisting of plowed fields, vineyards, pastures and woodlands. Here every variety of domestic and wild animal roamed about. Parts of the house were overlaid with gold and studded with precious stones and mother of pearl. All the dining rooms had ceilings of fretted ivory, the panels of which could slide back and let a rain of flowers, or of perfume from hidden sprinklers, fall on his guests. The main dining room was circular, and its roof revolved slowly, day and night, in time with the sky. Sea water, or sulfur water, was always on tap in the baths.

The gemstones, perfumes, and rotating ceiling have long since disappeared, but archaeologists have uncovered an octagonal room with smaller rooms radiating from it. The roof was a dome with a huge hole or "oculus" in the center to let in light. Slits in the sides of the room also let in light, but they were positioned behind supports that subtly hid the light source from the visitor to the room.
There were grand paintings, fountains, ceiling decorations, and elaborate furnishings. Suetonius says:

When the palace had been decorated throughout in this lavish style, Nero dedicated it and condescended to remark, "Good, now I can at last begin to live like a human being."

Romans were indeed impressed with this manse, but did not approve of it. Nero's lifestyle made his house an easy target for criticism. The Domus Aurea became a symbol of the decadence that motivated Nero's immoral acts. The artificial lake, the rotating ceiling, the misting unguents, and the 120­foot tall statue of Nero himself all reminded the Romans of the outlandish extravagance of Nero's regime.
The ancient historian Tacitus wrote that Nero had transgressed the sacred boundaries of nature by building out of the ashes of a burned city a country villa complete with artificial lakes, transplanted vineyards, and imported animals.
After Nero's suicide in 68 A.D., the artificial lake was drained. The resulting amphitheater would later be called the Colosseum, not because of its size but because of the colossal 120­foot statue that stood outside. This statue that had represented Nero was renamed Helios in honor of the god of the sun lest Nero receive posthumous honor.