History of the Peloponnesian War

But Nicias desired that the Athenians might keep their watch upon Megara in that island as being nearer and no more at Budorum and Salamis, to the end that the Peloponnesians might not go out thence with their galleys undescried nor send out pirates as they had formerly done, and to prohibit the importation of all things to the Megareans by sea.

Wherefore, when he had first taken two towers that stood out from Nisaea, with engines applied from the sea, and so made a free entrance for his galleys between the island and the firm land, he took it in with a wall also from the continent in that part where it might receive aid by a bridge over the marshes; for it was not far distant from the main land.

And, that being in few days finished, he built a fort in the island itself and, leaving there a garrison, carried the rest of his army back.

It happened also about the same time of this summer, that the Plataeans, having spent their victual and being unable longer to hold out, yielded their city in this manner to the Peloponnesians.