Answer
Thermopylae was the famous last stand of Leonidas I, the king of Sparta. In 480 BC, Leonidas led a force of 300 Spartans and 700 Thespians to defend the narrow pass of Thermopylae against a massive Persian army. Despite being outnumbered, the Greeks held off the Persians for three days, inflicting heavy losses. Eventually, the Persians were able to outflank the Greeks and force them to retreat.