The Athenian generals, however, saw that some obstacle had arisen and that they would not be able to take the city by force, and therefore at once began to invest Nisaea with a wall, thinking that, if they could take this town before any succour came, Megara also would soon capitulate.
A supply of iron quickly arrived from Athens, as well as stonemasons and whatever else was needed. Beginning then at the part of the fortification which they already held and building a cross-wall on the side of it facing Megara, from that point they built out on either side of Nisaea as far as the sea, the army apportioning among them the ditch and the walls and using stones and bricks from the suburbs. Moreover, they cut down fruit-trees and forest-wood and built stockades wherever they were needed; and the houses of the suburbs with the addition of battlements of themselves furnished a rampart.