But Belisarius, when he heard that the Goths were marching against him with their whole force, was in a dilemma. For he was unwilling, on the one hand, to dispense with the troops of Constantinus and Bessas, especially since his army was exceedingly small, and, on the other, it seemed to him inexpedient to abandon the strongholds in Tuscany, lest the Goths should hold these as fortresses against the Romans. So after considering the matter he sent word to Constantinus and Bessas to leave garrisons in the positions which absolutely required them, large enough to guard them, while they themselves with the rest of the army should come to Rome with all speed. And Constantinus acted accordingly. For he established garrisons in Perusia and Spolitium, and with all the rest of his troops marched off to Rome. But while Bessas, in a more leisurely manner, was making his dispositions in Narnia, it so happened that, since the enemy were passing that way, the plains in the outskirts of the city were filled with Goths. These were an advance guard preceding the rest of the army; and Bessas engaged with them and unexpectedly routed those whom he encountered and killed many; but then, since he was overpowered by their superior numbers, he retired into Narnia. And leaving a garrison there according to the instructions of Belisarius, he went with all speed to Rome, and reported that the enemy would be at hand almost instantly. For Narnia is only three hundred and fifty stades distant from Rome. But Vittigis made no attempt at all to capture Perusia and Spolitium; for these places are exceedingly strong and he was quite unwilling that his time should be wasted there, his one desire having come to be to find Belisarius not yet fled from Rome. Moreover, even when he learned that Narnia also was held by the enemy, he was unwilling to attempt anything there, knowing that the place was difficult of access and on steep ground besides; for it is situated on a lofty hill. And the river Narnus flows by the foot of the hill, and it is this which has given the city its name. There are two roads leading up to the city, the one on the east, and the other on the west. One of these is very narrow and difficult by reason of precipitous rocks, while the other cannot be reached except by way of the bridge which spans the river and provides a passage over it at that point. This bridge was built by Caesar Augustus in early times, and is a very noteworthy sight; for its arches are the highest of any known to us.So Vittigis, not enduring to have his time wasted there, departed thence with all speed and went with the whole army against Rome, making the journey through Sabine territory. Feb. 21, 537 a.d.And when he drew near to Rome, and was not more than fourteen stades away from it, he came upon a bridge over the Tiber River.[87] There a little while before Belisarius had built a tower, furnished it with gates, and stationed in it a guard of soldiers, not because this is the only point at which the Tiber could be crossed by the enemy (for there are both boats and bridges at many places along the river), but because he wished the enemy to have to spend more time in the journey, since he was expecting another army from the emperor, and also in order that the Romans might bring in still more provisions. For if the barbarians, repulsed at that point, should try to cross on a bridge somewhere else, he thought that not less than twenty days would be consumed by them, and if they wished to launch boats in the Tiber to the necessary number, a still longer time would probably be wasted by them. These, then, were the considerations which led him to establish the garrison at that point; and the Goths bivouacked there that day, being at a loss and supposing that they would be obliged to storm the tower on the following day; but twenty-two deserters came to them, men who were barbarians by race but Roman soldiers, from the cavalry troop commanded by Innocentius.[88] Just at that time it occurred to Belisarius to establish a camp near the Tiber River, in order that they might hinder still more the crossing of the enemy and make some kind of a display of their own daring to their opponents. But all the soldiers who, as has been stated, were keeping guard at the bridge, being overcome with terror at the throng of Goths and quailing at the magnitude of their danger, abandoned by night the tower they were guarding and rushed off in flight. But thinking that they could not enter Rome, they stealthily marched off toward Campania, either because they were afraid of the punishment the general would inflict or because they were ashamed to appear before their comrades.