History of the Peloponnesian War

But the wall was completed to only about half of the height he originally intended, for what he wished was to be able to repel the assaults of the enemy by the very height and thickness of the wall, and he thought that a few men, and these the least effective, would suffice to guard it, while all the rest might man the ships.

For Themistocles devoted himself particularly to the navy, because, as it seems to me, he had observed that the approach of the King's forces was easier by sea than by land; and he thought that the Peiraeus would prove more serviceable than the upper city, and often advised the Athenians, if ever they were hard pressed on land, to go down to the Peiraeus, and resist all their opponents with their fleet.

It was in this way, then, that the Athenians got their walls built, and came to be engaged upon their other fortifications, immediately after the withdrawal of the Persians.

Meanwhile Pausanias son of Cleombrotus was sent out from Lacedaemon in command of the Hellenes with twenty ships from Peloponnesus, accompanied by thirty Athenian ships and a multitude of other allies.