The last Praenestine expansion in territory had a motive beyond the acquisition of land, for it was also important from a strategical point of view. It will be remembered that the second great trade route which came into the Roman plain ran past Zagarolo, Passerano, and Corcolle.[28] This road runs along a valley just below ridges which radiate from the mountain on which Praeneste is situated, and thus bordered the land which was by nature territory dependent upon Praeneste.[29] So this final extension of her domain was to command this important road. With the carrying out of this project all the ridges mentioned above came gradually into the possession of Praneste, as natural, expedient, and unquestioned domain, and on the ends of those ridges which were defensible, dependent towns grew up. There was also a town at Cavamonte above the Maremmana road, probably a village out on the Colle dell'Oro, and undoubtedly one at Marcigliano, or in that vicinity. We have already seen that across a valley and a stream of some consequence there is a ridge not at all connected with the mountain on which Praeneste was situated, but belonging rather to Valmontone, which was better suited for neutral ground or to act as a buffer to the southeast. We turn to mention this ridge again as territory topographically outside Praeneste's domain, in order to say more forcibly that one must cross still another valley and stream before reaching the territory of Cave, and so Cave, although dependent upon Praeneste, by reason of its size and interests, was not a dependent city of Praeneste, nor was it a part of her domain.[30] In short, to describe Praeneste, that famous town of Latium, and her domain in a true if homely way, she was an ancient and proud city whose territory was a commanding mountain and a number of ridges running out from it, which spread out like a fan all the way from the Fosso dell'Ospedalato (the depression shown in plate II) to the Sabine mountains on the north. THE CITY, ITS WALLS AND GATES. The general supposition has been that the earliest inhabitants of Praeneste lived only in the citadel on top of the hill. This theory is supported by the fact that there is room enough, and, as will be shown below, there was in early times plenty of water there; nevertheless it is certain that this was not the whole of the site of the early city.