The most conspicuous outlying hill of the volcanic district not far from Gabii is that of La Colonna, about three miles below Rocca Priora. It stands apart from the rest of the range, and is easily seen from Rome. From Strabo’s description of the site of Labicum there can be but little doubt that this hill must be considered to be the place to which he refers in his account of the Via Labicana. “That road,” he says, “begins at the Esquiline Gate, at which the Prænestine Road also leaves the city, and leaving both this latter and the Esquiline plain on the left, proceeds for more than a hundred and twenty stadia (fifteen and a half Roman miles) till it reaches Labicum, an old, dismantled city, lying on a mount. The road leaves it and Tusculum on the right, and ends at the station called ad Pictas, where it joins the Latin Road.” There are no ancient ruins now on the spot. In Strabo’s time it was apparently ruined and deserted, and at an earlier date Cicero says that it was difficult to find any inhabitant to represent Labicum at the Feriæ Latinæ. It seems probable, therefore, that it suffered severely in the civil wars of Sylla and Marius, and did not recover itself until the establishment of an imperial villa there gave it some importance. [Sidenote: Præneste.] Beyond La Colonna, the ancient Labicum, by far the most important place on the Æquian frontier was the strong fortress-town of Præneste, now Palestrina, which commands the passage from Latium into the valley of the Sacco. Præneste is placed on one of the projecting spurs of the mountainous district which intervenes between the Anio and the Sacco. Standing, as the city does, more than 2100 feet above the sea level, it forms a very conspicuous object in the view from the hills of Rome. After its eventful history as the great border fortress of Latium, we can only wonder that it has been found possible to restore the ancient plan of Præneste with tolerable accuracy, as has been done by Nibby and other archæologists. The modern town, an agglomeration of filthy narrow alleys, occupies little more than the space on which stood the great Temple of Fortune and its approaches. Nearly a mile distant from this, on the summit of the hill, stood the citadel united with the town by two long walls of polygonal masonry, traces of which are still to be seen, though they do not rise to any height above the ground. The site of the citadel is now occupied by a wretched little suburb called Borgo di S. Pietro, and by a ruined mediæval castle of the Colonnas built in the style called opera Saracenesca. On the side towards the town the walls of the citadel are still easily traced, and present admirable examples of polygonal structure, rising in some places to a considerable height. On the other side, where the steepness of the hill made artificial defences less necessary, the walls have almost disappeared.