Introduction: maritime introspections

Abstract

Janus, the two-headed God, looks out and looks in. Down the Palatine hill in Rome, next to the church of San Giorgio in Velabro, not far from where Romulus and Remus were said to have been found by the she-wolf, stands the Arch of Janus Quadrifrons. It was erected in the early fourth century under the reign of Constantine, at the northeastern tip of the Forum Boarium, the cattle market of ancient Rome. Sixteen metres high and twelve metres wide, with an archway on each of its four sides, this arch of Janus served as a monument and a gateway to the commercial centre of the Roman capital. The Forum Boarium dates back to the time of the Republic and is strategically located between the Palatine, Capitoline and Aventine hills, and the Tiber River. Janus, the God of passageways, of going in and out, was venerated in Rome from time immemorial. In the Forum Romanum, the temple of Janus geminus had been consecrated by Numa Pompilius, the second king of Rome, in the seventh century BCE. Its door remained open in times of war, and closed, if only very rarely, in times of peace. The God with two faces, one looking outwards, the other looking inwards, presided over the fortunes of a growing territorial and commercial empire. As it was required to channel increasing amounts of goods to feed the capital, the Portus Tiberinus, built under Servius Tullius in the sixth century next to the Forum Boarium, became congested. The seven hills are situated some twenty miles inland from the sea. In the first century BCE, the fortress at Ostia on the coast was further developed into a city. The need for a deep harbour port remained, and under the reign of Claudius digging eventually commenced.1 The Portus,