CAIRO, July 4 -- A deacon named Tisous left his name on the wall of a mudbrick house in the Dakhla Oasis around 350 CE. Then the city around his house disappeared into the sand, and he disappeared with it, and for sixteen centuries nobody came looking. Egyptian archaeologists announced on Thursday that they had found him.

The Supreme Council of Antiquities confirmed the discovery of an entirely intact Byzantine residential city at the Ain el-Sabil site in Egypt's New Valley Governorate, a settlement built during the reign of Emperor Constantius II, who ruled from 337 to 361 CE, and preserved beneath the desert floor with an unusual degree of completeness. Streets still run north to south, intersecting east to west along the grid its inha...