The fate of Athens now hung upon a thread. Had its people fled to a distant land, one of the greatest chapters in the history of the world would never have been written. But now Themistocles, to whom Athens owed its fleet, came forward as its savior. If the oracle, he declared, had meant that the Greeks should be destroyed, it would have called Salamis, where the battle was to be fought, "wretched Salamis." But it had said "divine Salamis." What did this mean but that it was not the Greeks, but the enemies of Greece, who were to be destroyed? He begged his countrymen not to desert their country, but to fight boldly for its safety. Fortunately for Athens, his solution of the riddle was accepted, and the city set itself diligently to building more ships, that they might have as powerful a fleet as possible when the Persians came. But not only Athens was to be defended; all Greece was in peril; the invaders must be met by land as well as by sea. Greece is traversed by mountain ranges, which cross from sea to sea, leaving only difficult mountain paths and narrow seaside passes. One of these was the long and winding defile to Tempe, between Mounts Olympus and Ossa, on the northern boundary of Greece. There a few men could keep back a numerous host, and thither at first marched the small army which dared to oppose the Persian millions, a little band of ten thousand men, under the command of a Spartan general. But they did not remain there. The Persians were still distant, and while the Greeks awaited their approach new counsels prevailed. There was another pass by which the mountains might be crossed,--which pass, in fact, the Persians took. Also the fleet might land thousands of men in their rear. On the whole it was deemed best to retreat to another pass, much farther south, the famous pass of Thermopylae. Here was a road a mile in width, where were warm springs; and at each end were narrow passes, called gates,--the name Thermopylae meaning "hot gates." Adjoining was a narrow strait, between the mainland and the island of Euboea, where the Greek fleet might keep back the Persian host of ships. There was an old wall across the pass, now in ruins. This the Greeks rebuilt, and there the devoted band, now not more than seven thousand in all, waited the coming of the mighty Persian host. It was in late June, of the year 480 B.C., that the Grecian army, led by Leonidas, king of Sparta, marched to this defile. There were but three hundred Spartans[3] in his force, with small bodies of men from the other states of Greece. The fleet, less than three hundred ships in all, took post beside them in the strait. And here they waited while day by day the Persian hordes marched southward over the land.