In ancient and modern times, Egypt has owed its existence to the Nile River, with its fertile valley stretching like a long, narrow green ribbon through the parched desert regions of northeastern Africa. “Lower Egypt” comprised the broad Delta region where the Nile waters fan out before emptying into the Mediterranean Sea, at one time through at least five separate branches, today by only two. From the point where the Nile’s waters diverge (in the region of modern Cairo) to the seacoast is about 160 km (100 mi). The site of ancient Heliopolis (Biblical On) is found a short distance N of Cairo, while a few miles S of Cairo lies Memphis (usually called Noph in the Bible). (Ge 46:20; Jer 46:19; Ho 9:6) To the S of Memphis began the region of “Upper Egypt,” extending up the valley all the way to the first cataract of the Nile at Aswan (ancient Syene), a distance of some 960 km (600 mi). Many scholars, however, consider it more logical to refer to the northern part of this section as “Middle Egypt.” In this entire region (of Middle and Upper Egypt) the flat Nile Valley rarely exceeds 20 km (12 mi) in width, and it is bounded on both sides by limestone and sandstone cliffs, which form the edge of the desert proper.

Economy dependent on Nile. Whereas today the desert regions lining the Nile Valley provide little or no vegetation to sustain animal life, the evidence is that in ancient times the wadis, or torrent valleys, contained many game animals hunted by the Egyptians. Still, rain was evidently scant and today is negligible (Cairo receiving perhaps 5 cm [2 in.] annually). Thus life in Egypt depended on the waters of the Nile.

The Nile’s sources take their rise in the mountains of Ethiopia and neighboring lands. Here seasonal rainfall was sufficient to swell the river’s flow, causing it to flood its banks in Egypt each year during the months of July to September. (Compare Am 8:8; 9:5.) This not only provided water for irrigation canals and basins but also deposited valuable silt to enrich the soil. So fertile was the Nile Valley, and also the Delta, that the well-watered region of Sodom and Gomorrah viewed by Lot was likened to “the garden of Jehovah, like the land of Egypt.” (Ge 13:10) However, the amount of inundation was variable; when low, production was poor and famine resulted. (Ge 41:29-31) The complete failure of the Nile inundations would represent a disaster of the first order, converting the country into a barren wasteland.​—Isa 19:5-7; Eze 29:10-12.