The adjoining Monastery belongs to the Cistercians. Only part of one wing is ancient. The library formerly contained many curious MSS., but most of these were lost to the basilica, when the collection was removed to the Vatican during the French occupation and the exile of Pius VII.
The garden of the monastery contains the ruin generally known as the Temple of Venus and Cupid, but considered by Dr. Braun to be the Sessorian Basilica or law-court, where the causes of slaves (who were allowed to appeal to no other court) were wont to be heard. Behind the monastery is the Amphitheatrum Castrense, attributed to the time of Nero, when it is supposed to have been erected for the games of two cohorts of soldiers, quartered near here. It is ingrafted into the line of the Honorian walls, and is best seen from the outside of the city. Its arches and pillars, with Corinthian capitals, are all of brick.
(On the left of the Via Sta. Croce, which leads hence to Sta. Maria Maggiore, is the gate of the Villa Altieri, chiefly remarkable for its grand umbrella pine, the finest in the city. Further, on the right, is a tomb of unknown origin, now used as a farm-house and a wine-shop.)
Turning to the right from the basilica, we follow a lane which leads beneath some fine brick arches of an aqueduct of the time of Nero, cited by Ampère,[286] as exemplifying the perfection to which architecture attained in the reign of this emperor, "by the quality of the bricks, and the excellence and small quantity of the cement." These ruins are popularly called the Baths of Sta. Helena.
Passing these arches we find ourselves facing the Porta Maggiore, formed by two arches of the Claudian Aqueduct, formerly known as the Porta Labicana, and Porta Prenestina, of which the former was closed in the time of Honorius, and has never been re-opened. Three inscriptions remain, the first relating to the building of the aqueduct by the Emperor Tiberius Claudius;—the second and third to its restoration by Vespasian and Titus. Above the Aqua Claudia flowed a second stream, the Anio Novus.
Outside the gate, only lately disclosed, upon the removal of constructions of the time of Honorius (the fragments of those worth preserving are placed on the opposite wall), is the Tomb of the Baker Eurysaces, who was also one of the inspectors of aqueducts. The tomb is attributed to the early years of the Empire. Its first storey is surmounted by the inscription: "EST HOC MONUMENTUM MARCEI VERGILEI EVRYSACES PISTORIS REDEMPTORIS APPARET." Its second storey is composed of rows of the mortars used in baking, placed sideways, and supporting a frieze with bas-reliefs telling the story of a baker's work, from the bringing of the corn into the mill to its distribution as bread. In the front of the tomb was formerly a relief of the baker and his wife, with a sarcophagus, and the inscription: "FUIT ATISTIA UXOR MIHEI—FEMINA OPTVMA VEIXSIT—QUOIVS CORPORIS RELIQUIÆ—QUOD SUPERANT SUNT IN—HOC PANARIO." This has been foolishly removed, and is now to be seen upon the opposite wall.
From this gate many pleasant excursions may be taken. The direct road leads to Palestrina by Zagarolo, and at 1½ mile from the gate passes, on the left, Torre Pignatarra, the tomb of Sta. Helena, whence the magnificent porphyry sarcophagus, now in the Vatican, was removed. The name is derived from the pignatte, or earthen pots, used in the building. Beneath it is a catacomb, now closed. The adjoining Catacomb of SS. Pietro e Marcellino contains some well preserved paintings; the most interesting is that of the Divine Lamb on a mound (from which four rivers flow as in the mosaics of the ancient basilicas), with figures of Petrus, Gorgonius, Marcellinus, and Tiburtius. At three miles from the gate the road reaches Centocellæ, whence, near the desolate tower called Torre Pernice, there is a most picturesque view of the aqueduct Aqua Alexandrina, built by Alexander Severus, with a double line of arches crossing the hollow. At five miles, on the right, is the Borghese farm of Torre Nuova, with a fine group of old stone pines.
The road which turns left from the gate leads by the Aqua Bollicante, where the Arvales sang their hymn, to the picturesque ruins of the Torre dei Schiavi, the palace of the Emperors Gordian (A.D. 238), adjoining which are the remains of a round temple of Apollo. This is, perhaps, one of the most striking scenes in the Campagna and—backed by the violet mountains above Tivoli—is a favourite subject with artists.
"Les Gordiens, très-grands personnages, furent de très-petits empereurs. Ils montrent ce qu'était devenu l'aristocratie romaine dégénérée. Le premier, honnête et pusillanime, comme le prouvent son élection et sa mort, était un peu replet et avait dans l'air du visage quelque chose de solennel et de théâtral (pompali vultu). Il aimait et cultivait les lettres. Son fils également se fit quelque réputation en ce genre, grâce surtout à sa bibliothèque de soixante mille volumes; mais il avait d'autres goûts encore que celui des livres: on lui donne jusqu'à vingt-deux concubines en titre, et de chacune d'elles, il eut trois ou quatre enfants. Il menait une vie épicurienne dans ses jardins et sous des ombrages délicieux: c'étaient les jardins et les ombrages d'une villa magnifique que les Gordiens avaient sur la voie Prénestine, et dont Capitolin, au temps duquel elle existait encore, nous a laissé une description détaillée. Le péristyle était formé de deux cents colonnes des marbres les plus précieux, le cipollin, le pavonazetto, le jaune et le rouge antiques. La villa renfermait trois basiliques et les thermes que ceux de Rome surpassaient à peine. Telle était l'opulence d'une habitation privée vers le milieu du troisième siècle de l'empire."—Ampère, Emp. ii. 328.