[381] Diodorus, however, is wrong in stating (xiii, 7) that the Athenians occupied the temple of Zeus Olympius and the polichnê, or hamlet, surrounding it, on the right bank of the Anapus. These posts remained always occupied by the Syracusans, throughout the whole war (Thucyd. vii, 4, 37). In regard to the works actually undertaken, the order followed by Nikias and Lamachus can be satisfactorily explained. Having established their fortified post on the centre of the slope of Epipolæ, they were in condition to combat opposition and attack any counter-wall on whichever side the enemy might erect it. Commencing in the first place the execution of the northern portion of the blockading line, they soon desist from this and turn their attention to the southern portion, because it was here that the Syracusans carried their two first counter-works. In attacking the second counter-work of the Syracusans, across the marsh to the Anapus, they chose a suitable moment for bringing the main fleet round from Thapsus into the Great Harbor, with a view to its coöperation. After clearing the lower ground, they probably deemed it advisable, in order to establish a safe and easy communication with their fleet, that the double wall across the marsh, from Epipolæ to the Harbor, should stand next for execution; for which there was this farther reason, that they thereby blocked up the most convenient exit and channel of supply for Syracuse. There are thus plausible reasons assignable why the northern portion of the line of blockade, from the Athenian camp on Epipolæ to the sea at Trogilus, was left to the last, and was found open, at least the greater part of it, by Gylippus.