The document summarizes the environment of ancient Greece and the battle of Thermopylae between Greek and Persian forces. It describes the mountainous terrain of Greece and tools/weapons used by Spartans and Athenians such as shields, helmets, swords, and spears. It then discusses how Greeks had to adapt to their environment by establishing separate city-states, building boats to trade by sea, and looking elsewhere for fertile farmland due to the difficult terrain. The battle of Thermopylae is referenced where a small Greek force delayed the larger Persian army in a mountain pass.