[Sidenote: Mausoleum of Augustus.]
Among the other buildings which Augustus erected, should not be omitted the magnificent Mausoleum, or the tomb of the imperial family at the northern part of the Campus Martius, near which lay the remains of Sulla and of Caesar, and which remained the burial-place of his family down to the time of Hadrian. [Transcriber's Note: Lengthy footnote relocated to chapter end.] He also brought from Egypt the obelisk which now stands on Mount Citorio, and which was placed in that receptacle for monuments—the Campus Martius.
[Sidenote: Imperial palace.]
Tiberius did but little for the improvement of his capital beyond erecting a triumphal arch, in commemoration of the exploits of Germanicus, on the Via Sacra, and establishing the Praetorian Camp near the Servian Agger. Caligula extended the imperial palace, and began the Circus Neronis in the gardens of Agrippa, near where St. Peter's now stands.
[Sidenote: Claudian aqueduct.]
Claudius constructed the two noble aqueducts, the Aqua Claudia and Arno Novis,—the longest of all these magnificent Roman monuments,—the latter of which was fifty-nine miles in length, and some of its arches were one hundred and nine feet in height.
Nero still further extended the precincts of the imperial palace, and included the Esquiline. The great fire which occurred in his reign, A.D. 65, and which lasted six days and seven nights, destroyed some of the most ancient of the Roman structures surrounding the Palatine, and very much damaged the Forum, to say nothing of the statues and treasures which perished. But the city soon arose from her ashes more beautiful than before. The streets were laid out on a more regular plan and made wider, the houses were built lower, and brick was substituted for wood.
[Sidenote: The Imperial Palace.]
The great work of Nero was the construction of the Imperial Palace on the site of the buildings which had been destroyed by the fire. He gave it the name of Aurea Domus, and, if we may credit Suetonius, [Footnote: Suet. Ner., 31.] its richness and splendor surpassed any other similar edifice in ancient times. It fronted the Forum and Capitol, and in its vestibule stood a colossal statue of the emperor, one hundred and twenty feet high. The palace was surrounded by three porticoes, each one thousand feet in length. The back front of the palace looked upon the artificial lake, afterwards occupied by the Flavian Amphitheatre. Within the area were gardens and vineyards. It was entirely overlaid with gold, and adorned with jewels and mother-of-pearl. The supper rooms were vaulted, and the compartments of the ceiling, inlaid with ivory, were made to revolve and scatter flowers upon the banqueters below. The chief banqueting-room was circular, and perpetually revolved in imitation of the motion of the celestial bodies. There are scarcely no remains of this extensive palace, which engrossed so large a part of the city, and which covered the site of so many famous temples and palaces, and which exhausted even the imperial revenues, great as they were, even as Versailles taxed the magnificent resources of Louis XIV., and St. Peter's obliged the Popes to appeal to the contributions of Christendom.
[Sidenote: Temple of Peace.]