The little town prepared to defend herself against the enemy, sending away the women and children to a place of safety. A hundred women slaves only were kept to cook and wash for the garrison, which was small. Yet few in number as they were, the doughty citizens withstood the attacks of the Spartans for two years.
When Archidamus ordered his men to raise a mound as high as the wall around the town, the Plataeans at once added to the height of their defences. They also dug beneath the mound of the enemy, and so undermined it that it was continually sliding down.
Then lest the walls should at length be scaled by the enemy, the citizens built an inner wall to protect the city yet more strongly.
Often the little garrison looked wistfully for the help that Athens had assured them would be sent, but month after month passed and no help came from the plague-stricken city. Yet the Plataeans did not dream of surrender.
Archidamus was in despair, for he knew that his soldiers were seldom able to take a walled town. His pride was hurt at the thought of being beaten by a mere handful of men. He had with him the whole Peloponnesian army, yet a garrison of five hundred had been able to defy all his efforts to capture the city.
The king determined, since he could not take the town by assault, to starve it into submission. So he now ordered two great walls to be built round the city, placing on them here and there towers or battlements. The walls were a certain space apart, and this space was covered over, so that the soldiers could live in it as in a camp, while armed sentinels paced up and down on the roof.
When the second year of the siege began, food grew scarce in Plataea. Either the little garrison must force its way out or die of hunger. To escape, the soldiers would have to scale the wall, without attracting the attention of the sentinels, and reach the ground on the other side.
More than half the garrison resolved to stay where it was, but about two hundred determined to make the perilous attempt.
So one cold, dark night in the month of December, when the sentinels had retreated into the towers for shelter, the brave two hundred stole out of the town, carrying ladders on their backs. They wore little clothing, that they might climb and run the easier. That they might step the more quietly their right feet were bare, while on the left each wore a shoe to keep him from slipping in the mud.
Stealthily they made their way across a ditch and reached the wall unseen, unheard. Twelve of the bravest scaled the wall and killed the sleepy sentinels, who had sought shelter in the towers from a storm of wind and rain.