Victory at Thermopylae meant that all Boeotia fell to Xerxes; the two cities that had resisted him, Thespiae and Plataea, were captured and razed. Attica was also left open to invasion, and the remaining population of Athens was thus evacuated, with the aid of the Allied fleet, to Salamis.[123] The Peloponnesian Allies began to prepare a defensive line across the Isthmus of Corinth, building a wall, and demolishing the road from Megara, thereby abandoning Athens to the Persians.[124] Athens thus fell; the small number of Athenians who had barricaded themselves on the Acropolis were eventually defeated, and Xerxes then ordered Athens to be torched.[125]