Hey there!
The Battle Of Marathon was an intense battle of the Greco-Persian wars that was about sacrifice and never giving up.
The Greeks, as always, had a smart plan. They fought on a thin, hard to fit through mountain pass and they used phalanxes and defeated the Persian Hoplites and Immortals. They thought they had victory, but eventually, the way around the pass was given to King Xerxes of Persia by a Greek traitor and the Persians one.