The Greeks determined to make a stand at the pass of Thermopylae, which forms the entrance from northern into southern Greece. This pass lies between Mount OEta and the sea. It is about a mile in length. At each of its extremities the mountains approach so near the sea as to leave barely room for the passage of a single carriage. The northern, or, to speak more properly, the western Gate, was close to the town of Anthela, where the Amphictyonic council held its autumnal meetings; while the southern, or the eastern Gate, was near the Locrian town of Alpeni. These narrow entrances were called Pylae, or the Gates. The space between the gates was wider and more open, and was distinguished by its hot springs, from which the pass derived the name of Thermopylae, or the "Hot-Gates." The island of Euboea is here separated from the mainland by a narrow strait, which in one part is only two miles and a half in breadth; and accordingly it is easy, by defending this part of the sea with a fleet, to prevent an enemy from landing troops at the southern end of the pass. The Grecian fleet, under the command of the Spartan Eurybiades, took up its station off that portion of the northern coast of Euboea which faces Magnesia and the entrance to the Thessalian gulf and which was called Artemisium, from a neighbouring temple of Artemis (Diana). It was, however, only a small land-force that was sent to the defence of Thermopylae. When the arrival of Xerxes at Therma became known, the Greeks were upon the point of celebrating the Olympic games, and the festival of the Carnean Apollo, which was observed with great solemnity at Sparta and in other Doric states. The Peloponnesians therefore sent forward only 300 Spartans and 3000 hoplites from other Peloponnesian states, under the command of the Spartan king Leonidas, a force which they thought would be sufficient to maintain the pass till the festivals were over. In his march northwards Leonidas received additions from the Thespians, Phocians, and Locrians, so that he had under his command at Thermopylae about 7000 men.