Porta San Sebastiano (c350). The Porta San Sebastiano is the largest and one of the best-preserved gates passing through the Aurelian Walls in Rome. Originally known as the Porta Appia, the gate sat astride the Appian Way, the regina viarum, which originated at the Porta Capena in the Servian Wall. During the Middle Ages probably it was also called Accia, a name whose etymology is quite uncertain, but arguably associated with the river Almone, called acqua Accia, that flowed nearby. A document ca. AD 1434 calls it Porta Domine quo vadis. The present name is attested only since the second half of 15th century, due to the vicinity to the Basilica of San Sebastiano and its catacombs. The original structure was constructed by Aurelian ca. AD 275 and included a double-arched opening surmounted by bow windows and two semi-cylindrical towers. The façade was faced with travertine. After a later restoration, the towers were enlarged, increased, and linked, through two parallel walls, to the preexisting Arch of Drusus. In AD 401-402 Emperor Honorius reshaped the gate with a single fornix and a higher attic with two rows of six bow windows each; it was also provided with an uncovered chemin de ronde with merlons. The bases of the towers were incorporated within two square-plan platforms, faced with marble. A later modification yielded the gate's present form, in which a floor has been added to the whole structure, towers included. Due to the absence of the usual plate commemorating the works, some archaeologists doubt that the work has not been carried out by Honorius, who left panegyric epigraphs on any other restored part of the walls or the gates. The latch was released by means of two wooden gates and a shutter that rolled, through still visible grooves, from the control room placed above, whose supporting travertine shelves are still existing. Some notches on the jambs could indicate that wooden beams were also employed to strengthen the latch. Because of the importance of the Appian Way, that just here entered the town, the whole area was concerned with great traffic movements, especially during ancient Rome. It seems that close to the door there was an area designed for parking of the private means of transport that accessed the town from here; it was what now could be defined a park and ride, since the transit of private means within the town was usually not allowed. This rule probably was effective also for the members of the Imperial family, whose private means were parked in a reserved area just a little farther at the beginning of the Appian Way. Some lumps, still visible on the travertine upholstery in the basis of the monument, are quite interesting: they could be reference marks for the stone cutters. According to historian Antonio Nibby, in the centre of the arch of the hate, on the inner side, there is a carved Greek cross inscribed into a circumference, with an inscription in Greek, dedicated to Saint Conon and Saint George, dating back to 6th-7th century, but today there is no visible trace left. On the right jamb of the gate there is also a carved figure portraying Archangel Michael killing a drake, alongside of a blackletter inscription written in Medieval Latin, that commemorates the battle fought on 29 September 1327 by Roman Ghibelline militiamen of the Colonnas, led by Giacomo de' Pontani, against the Guelph army of Robert of Anjou, King of Naples, led by John II and Gaetano Orsini: ANNO DNI MC XVII INDICTIONE XI MENSE SEPTEM BRIS DIE PENULTIM A IN FESTO SCI MICHA ELIS INTRAVIT GENS FORASTERA MURI A ET FUIT DEBELLA TA A POPULO ROMA NO QUI STANTE IA COBO DE PONTIA NIS CAPITE REG IONIS In addition to such remains, that are interesting from an historic viewpoint, the whole monument is noteworthy also for the abundance of graffiti traces that, though not official at all, provide evidence of the daily life that occurred around the gate along the centuries. On the left jamb, in front of Archangel Michael, there are several crosses and a christogram, probably carved by pilgrims; there are also several Italian and foreign names and dates, that can be deciphered back to 1622; somebody also carved a kind of road direction to Porta San Giovanni or St. John Lateran, addressed to foreign wanderers and still visible just outside the gate, on the left: DI QUA SI VA A S. GIO, interrupted by something or someone; as well as other signs and writing hard to decipher, such as the engraving LXXV DE L, on the tower on the right. On 5 April 1536, on the occasion of the entry in Rome of Emperor Charles V, Antonio da Sangallo the Younger changed the gate into a real triumphal arch, decorating it with statues, columns and friezes, as well as arranging-through the demolition of former buildings-a triumphal way up to the Roman Forum.