And here, as always, it was not without betrayal. What motivated the Malian Ephialtes, who told Xerxes about the secret path, is not known for sure. But definitely nothing new: money, love, power. Anyway, on the third day of the battle, the Persians began to enter the Greeks from the rear. To save the people, Leonid ordered most of the army to retreat, remaining to fight to the end with a detachment of 300 Spartans and the militia of Thebes who refused to leave.
Stones, arrows, fire, swords... Everything was used, but the Hellenes stood to the death, and all of them died in that battle. More than 20 thousand Persians died, including two brothers of Xerxes himself.
Of course, you can talk for a long time on the topic 'what if'. If the Greeks had held out longer, the Persians would have started a food crisis, because it was almost impossible to supply food and water to a remote mountainous area. If not for the betrayal of Ephialt (killed, by the way, soon paid by the 'special agent' Athenad), perhaps the Spartans would have been able to hold the gorge and survive.
One way or another, but the names of all three hundred soldiers of Sparta, led by King Leonid, are remembered by the whole of Hellas, paying tribute to their courage and honor.