One seeks a reason for the location of this holy place at such a distance from the city. Holm, the German historian of Sicily, argues with some plausibility that this was no mere suburb of Syracuse, but the original Syracuse itself. In the first place, the list of the citizens of Syracuse was kept here down at least to the time of the Athenian invasion. In the second place, tradition, which, when rightly consulted, tells so much, says that Archias, the founder of Syracuse, had two daughters, Ortygia and Syracusa, which may point to two co-ordinate settlements, Ortygia and Syracuse; the latter, which was on this temple plateau, being subsequently merged in the former, but, as sometimes happens in such cases, giving its name to the combined result. Besides these temple ruins there are many more foundations that tell a more or less interesting story. Then there are remains of the ancient city that can never be ruined: for instance, the great stone quarries, pits over a hundred feet deep and acres broad, in some of which the Athenian prisoners were penned up to waste away under the gaze of the pitiless captors; the Greek theatre, cut out of the solid rock; the great altar of Hiero II., six hundred feet long and about half as broad, also of solid rock. Then there is the mighty Hexapylon, which closed the fortifications of Dionysius at the northwest at the point where they challenged attack from the land side. With its sally-ports and rock-hewn passages, some capacious enough to quarter regiments of cavalary, showing holes cut in the projecting corners of rock, through which the hitch-reins of the horses were wont to be passed, and its great magazines, it stands a lasting memorial to the energy of a tyrant. But while this fortress is practically indestructible, an impregnable fortress is a dream incapable of realization. Marcellus and his stout Romans came in through these fortifications, not entirely, it is true, by their own might, but by the aid of traitors, against whom no walls are proof.