The western shore of the Dead Sea, the most remarkable natural feature in Palestine (fig. 4), is a strip of flat or very gently sloping land, mostly barren, its parched surface seamed with a wrinkled pattern of erosion channels. The strip represents in part the old bed of the lake, once larger than now, and in part the spill of detritus from the rocky cliffs which tower above it. These precipitous heights form an almost unbroken wall some 300 ft. high extending from Qumran to Sdom, being patterned in high relief only by the few wadis which bite through them and carry the rare but torrential winter rains. The cliffs themselves are but the floor of the plateau through which the Jordan valley has opened its deep and famous rift, reaching a depth of over a thousand feet below Mediterranean sea-level; and from the plateau itself rises the mountainous, pitiless desert of Judah, stretching to Hebron 21 miles westward and draining eastwards towards the rift-valley. Where the eastward face of the cliffs is cut by water-courses it is carved into promontories, but in the main these constitute an integral part of wide sweeps of hinterland and are not positions of strength. At one point only (fig. 5) do two wadis flow close together and then divide, to tear out deep ravines behind a promontory, and almost to cut it off on the landward side. The spot in question is Masàda (pl. XVI), a lozenge-shaped table-mountain, 730 yds. long and 215 yds. wide overall, lofty, isolated and to all appearance impregnable.