THERMOPYLÆ, a narrow pass or defile, between the Sinus Malacens on the east, and a steep branch of Mount Cera, covered with unpassable woods, on the west; leading from Thessaly to Locris and Boeotia. These mountains divide Greece in the middle, in the same manner as the Apennine does Italy; forming one continued ridge from Leucate on the west, to the sea on the east, with thickets and rocks interspersed. The valley is of small breadth, and completely occupied by a marsh, through which it is impossible for horse or foot to penetrate. Through the middle of this marsh a paved road was made by the Greeks, which still remains, and affords the only path to Greece from Thessaly. The Thermes or hot springs, from which the place had its name, are near the narrowest part of the pass; and their temperature was found by Dr Clarke to be 111 degrees. At the south entrance of the defile is a small eminence, on which he found a tumulus, with the remains of a massive pedestal of red breccia much time-worn, and evidently the tomb of the 300 Spartans to whose immortal memories this monument was consecrated. The rising ground on which the monument stands is the spot where the Spartans fell. The remains of the wall which shut up the pass are also yet visible.