CERCASO´RUM or CERCASO´RA(Κερκάσωρον, Hdt. 2.15, 17, 97; Κερκάσουρα, Strab. 18. p. 806; Mela, 1.9.2: El Arkas), was, from its position, as the key of Middle and Lower Egypt, a town of great importance, both in a military and a commercial point of view. Cercasorum stood in lat. 30° 3′ N., at the apex of the Delta, and on the western or Canobic arm of the Nile. At this point, about ten miles below Memphis, the Nile ceases to be a simple stream, and branches off into numerous channels, while the hills which throughout the Thebaid and the Heptanomis embosom or skirt its banks, here diverge right and left, and sink gently down upon the Deltaic level. The Delta, in the present day, commences 6 or 7 miles lower down the river, at Batn-el-Baharah. (Rennell's Geog. of Herod. vol. 2. p. 133.)
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