“Arx Ianiculensis”

As a strategic high point outside the city, the *Ianiculum was said to have been walled at an early date by Ancus Marcius, and connected to the main city by the *Pons Sublicius (Livy 1.33.6; Dion. Hal., Ant. Rom. 3.45.1-2). This early settlement on the Ianiculum was known as Aineias (Dion. Hal., Ant. Rom. 1.73.3) or Antipolis (Pliny, NH 3.68; cf. Liverani 1996), and the modern term “Arx Ianiculensis” (Platner–Ashby 55) has been applied based upon sources that refer to this hill as an arx, or citadel (Ov., Fast. 1.245; Verg., Aen. 8.355-58; Livy 1.33.6, 2.51.4). In the Republican period, a fortified garrison protected river traffic on the *Tiber (Dion. Hal., Ant. Rom. 3.45.1), and served as a look-out post to warn of potential enemy attacks when the comitia centuriata met in the *Campus Martius (Dio Cass. 37.28.1-3; Livy 39.15). It is generally thought that this fort stood on the ridge of the Ianicu-lum at the apex of the later Aurelian Wall, connected to the main city by the *Via Aurelia (Säflund 208, Platner–Ashby 274-75, Richardson). Unfortunately, the archaeological record preserves nothing of these fortifications. Richardson suggests that it was little more than a small fort or watchtower, but the ancient sources imply something much more substantial. This fortress probably corresponded roughly with the W tip of the later Aurelian Wall (Säflund 188, 208). It was used in an active military capacity as late as 43 B.C. (Dio Cass. 46.44.5, 46.45.2; App., B Civ. 3.91). Säflund posits that this fort was joined to the *Servian Wall by a set of two parallel walls leading to the *Pons Sublicius and to the S tip of the *Aventine (Säflund 188-90; accepted as a strong possibility by Coarelli 1995; id. 1996, 19). This theory is not supported by any physical evidence, only by literary sources. There is the metaphorical statement that the Ianiculum was ‘joined to the city’ by Ancus Marcius (Livy 1.33.6: coniungi urbi), often taken somewhat literally (Liverani 1996; Coarelli 1996, 17). The crucial passage for Säflund is Appian’s statement that during the civil war of 87 B.C. Marius ‘entered the city’ (ἐς τὴν πόλιν) via the Ianiculum (App., B Civ. 1.68; cf. Livy, Epit. 80; Flor. 2.8.13). Since Sulla occupied the Pons Sublicius with no difficulty in 88 B.C. (App., B Civ. 1.58), Säflund argues that these connecting walls were built when the entire Servian Wall was restored in 87 B.C. (App., B Civ. 1.66). In terms of logistics, Säflund’s time-frame is extremely tight — there were only a few months to repair and extend the wall — and manpower was also a problem at Rome at this time (App., B Civ. 1.66-68). Moreover, the Ianiculum held the same tactical importance with or without Säflund’s parallel walls. The Tiber was the main obstacle for Marius entering the heart of the city. If the Pons Sublicius was protected by walls, then the Ianiculum provided the only point of access to the river (Säflund 188-89). If there were no such walls, Marius could advance straight to the river, yet he first needed to control the Ianiculum in order to protect his rear. Since Appian’s narrative is not enhanced by the addition of Säflund’s walls or diminished by their omission, we cannot conclude either way.