The line of communication between the two seas was impassable during the reign of Cleopatra (31 b.c.).  It is believed by some that it was restored during the reign of the Roman emperor Trajan (98-117).  During this period the Pelusiac branch of the Nile was very low, the water having almost completely deserted this formerly well-filled course.  If Trajan, therefore, undertook to reopen the water way, he must have tapped the Nile much higher up, in order to reach a plentiful supply of water.  The old canal near Cairo, which elsewhere joined the line of the former canal on the way to the Bitter Lakes, was once called “Amnis Trajanus,” and from this it has been inferred that Trajan was really the builder, and that during his reign this canal was cleaned and rendered navigable.  As there is no further evidence than the name to prove that Trajan undertook so important an enterprise, the “Amnis Trajanus” was probably constructed during the Arabic period.

When Amr had conquered Egypt, according to another account, the caliph Omar ordered him to ship rich supplies of grain to Mecca and Medina, because during the pilgrimages these cities and often the whole of Hedjaz suffered severely from famine.  As it was extremely difficult to send large quantities of provisions across the desert on the backs of camels, it is supposed that to facilitate this transportation Omar ordered the construction of the canal from a point near Cairo to the head of the Red Sea.  On account of his forethought in thus providing for the pilgrims to the Hedjaz, Omar received the title of “Prince of the Faithful” (Emir el-Momeneen), which thenceforth was adopted by his successors in the caliphate.  One hundred and thirty-four years after this time, El-Mansur, the second caliph of the Abbasid dynasty, is said to have closed the canal to prevent supplies from being shipped to one of the descendants of Ali who had revolted at Medina.  Since that time it is probable that it has never been reopened, although there is a report that the Sultan Hakim rendered it available for the passage of boats in the year A.D. 1000, after which it was neglected and became choked with sand.  While not thereafter used for navigation, there were parts which during the time of the annual inundation of the Nile were filled with water, until Mehemet Ali prevented this.  The parts filled during the inundation extended as far as Sheykh Hanaydik, near Toussun and the Bitter Lakes.

The old canal which left the Nile at Cairo had long ceased to flow beyond the outskirts of the city, and the still more ancient canal from the neighbourhood of Bubastis, now known as the Wady Canal, extended only a few miles in the direction of the isthmus as far as Kassassin.  During the construction of the Suez Canal the need of supplying the labourers with fresh water was imperative.  The company, therefore, determined in 1861 to prolong the canal from Kassassin to the centre of the isthmus, and in the year 1863 they brought the fresh-water canal as