Only recent footprints remain in Cave 4, one of the 11 caves overlooking or near the Wadi Qumran, on the northwestern shore of the Dead Sea, where the Dead Sea Scrolls lay hidden for two millennia. The dry atmosphere of the limestone caves helped to preserve the approximately 800 parchment scrolls, most of which survive, however, only in thousands of fragments. The scrolls include portions of all the books of the Hebrew Bible except Esther, as well as sectarian texts and a variety of nonsectarian documents. Archaeologist Roland de Vaux dug the small trench at lower right while searching for scroll fragments, some 15,000 of which, belonging to nearly 600 different scrolls, were retrieved from this one cave.