“Well, of course, it’s the Flood,” Lady Woolley casually remarked when her husband’s excavation team uncovered an 8-foot-thick layer of soil that contained no evidence of human activity, sandwiched between two layers of pottery.a In the photo above, two Arab workmen stand beside part of what came to be known as “the Flood deposit.”

Sir Leonard Woolley excavated Ur, in southern Iraq, between 1922 and 1934. Below, he displays a second-millennium B.C.E. statuette discovered in one of the site’s many wayside shrines.

Woolley first discovered evidence of what he and his wife called the Biblical flood in 1929 in a small shaft. Acknowledging that “one could scarcely argue for the Deluge on the strength of a pit a yard square,” Woolley decided to cut a 75-by-60-foot pit, which eventually extended 64 feet down. As shown in his drawing of the various occupational layers discovered in the pit (below), the first eight layers, labeled A-H and running from 17 to 10 meters (55 by 33 feet) above sea level, contained mud-brick walls. These architectural ruins ended suddenly about 10 meters above sea level, and a 5.5-meter layer of broken pottery began. Scattered throughout this layer, Woolley discovered kilns and a potter’s wheel, leading him to suggest this had been a pot factory.

Directly beneath the pottery layer came the so-called Flood deposit, measuring up to 12 feet thick and dating to the mid-fourth-millennium B.C.E. (The only intrusions into this layer were later graves.) Woolley observed that the silt had been deposited all at once, was water-laid and matched that of the Middle Euphrates region. During the Deluge, he speculated, the overflowing Euphrates had deposited the soil here.

Below the Flood deposit appeared a layer of mud bricks, ashes and potsherds that Woolley attributed to the prehistoric, pre-Flood community. About 3 feet below sea level, all traces of human occupation ended.

Woolley later retracted his identification of the Flood stratum, arguing that the deposit was too old to have resulted from the Biblical Deluge. Nevertheless, it offers strong evidence of flooding during the regional wet period that may have inspired the Flood story of Genesis 7:6–8:14.