On the east it is fringed with craggy cliffs overhanging the valley, while its outward border, running aslant to the north-west, offers here and there deep bays in which lie the oases of Khârgeh and Dâkhleh (Great Oasis), Farâfreh (Tringtheos Oasis), and Siweh (Jupiter Ammon). The oasis of Bahriyeh (Small Oasis), north-east of Farâfreh, lies, on the contrary, in a depression entirely surrounded by the higher plateau.
At Assuân the course of the river is broken by the first cataract, where its waters rush between numberless more or less diminutive islands, the most famous of which is the island of Philæ above and Elephantine in front of Assuân. Their tombs, however, have since been discovered at Ûmm-el-Ga'âb, near Abydos, in the territory of the ancient This (Thinis), and the names of Menes, Zer, Usaphais, and Miebis have already been found.
Near Girgeh (Abydos) begins the Bahr-Yûsef, Joseph's Canal.
It was formerly a branch of the Nile; it runs parallel to the main stream at a distance of from 5 to 6 miles along the left bank, and empties into the Fayûm ( home of Arsinoe ).
In ancient times there were seven of these branches, five natural and two artificial.
Only two are now of importance for navigation, the Damietta (Tamiathis) and the Rosetta branches, both named for the towns near which they discharge into the sea.