Marathon, and Athens was more exposed than any other of the Greek
cities. During the ten years Athens raised and equipped as large an
army as her population would warrant. Every able-bodied man was
enrolled in the ranks. Food and military stores were collected, but
the chief means of defense was a novel one, and showed the desperate
nature of the conflict in which they were about to engage. Under the
wise direction of Themistocles they built a formidable fleet, so large
that in case of emergency the whole population of the city could
embark, and either remain afloat or take refuge on the neighboring
islands.

19. A congress of the cities had determined to oppose the approach of
Xerxes at some favorable place by a combined army. At the head of the
Maliac gulf there was a narrow pass, through which the Persians had to
go, the road running between a mountain and a swamp which stretched to
the sea; and at one place the swamp came so near the mountain that
there was hardly room for the road to run between. This is the famous
pass of Thermopylae; and here it was that a small army might block the
way against any number of the enemy. Across this pass a wall was
built, and behind it was posted the Greek army under the command of
Leonidas, the Spartan king. His forces consisted of three hundred
Spartans, seven hundred Thespians, and about four thousand more from
the various Grecian cities. The Persians approached, and for four days
waited, expecting to see the Greek army disperse at the very sight of
their formidable numbers. But as they were apparently not frightened,
on the fifth day the Persians made an attack. For two days the battle
continued, inflicting great losses upon the Persians, while the little
army of Leonidas, behind their fortifications, was scarcely injured.

20. On the third morning a renegade Greek showed Xerxes a path across