History of the Peloponnesian War

On the same day an Athenian galley that lay moored off the harbor was captured by the Syracusans.

After this the Syracusans and their allies began to carry a single wall, starting from the city, in a slanting direction up Epipolae, in order that the Athenians, unless they could hinder the work, might be no longer able to invest them.

Meanwhile the Athenians, having now finished their wall down to the sea, had come up to the heights; and part of their wall being weak, Gylippus drew out his army by night and attacked it.

However, the Athenians who happened to be bivouacking outside took the alarm and came out to meet him, upon seeing which he quickly led his men back again. The Athenians now built their wall higher, and in future kept guard at this point themselves, disposing their confederates along the remainder of the works, at the stations assigned to them.