History of the Peloponnesian War

Then the Peloponnesians, wishing to assist the aeginetans, sent over to aegina three hundred heavy-armed, who were before auxiliaries of the Corinthians and Epidaurians. And the Corinthians with their allies seized the heights of Geranea, and marched down into the Megarid, thinking that the Athenians would be unable to succour the Megareans, while a large force was absent at aegina and in Egypt; but that if they did assist them, they would raise the siege of aegina.

The Athenians, however, did not remove the army that was at aegina, but the oldest and the youngest of those who had been left behind in the city came to Megara under the command of Myronides.