MAREO´TIS or MAREI´A(ἡ Μαρεῶτιςor Μαρεία λίμνη, Strab. xvii. pp. 789—799 ; Μάρεια, Steph. B. s. v.;Mareotis Libya, Plin. Nat. 5.10. s. 11; Justin. 11.1), the modern Birket-el-Mariout, was a considerable lake in the north of the Delta, extending south-westward of the Canopic arm of the Nile, and running parallel to the Mediterranean, from which it was separated by a long and narrow ridge of sand, as far as the tower of Perseus on the Plinthinetic bay. The extreme western point of the lake was about 26 miles distant from Alexandreia; and on that side it closely bordered upon the Libyan desert. ‘At its northern extremity its waters at one time washed the walls of Alexandreia on their southern side, and before the foundation.of that city Mareotis was termed the Lake above Pharus. In breadth it was rather more than 150 stadia, or about 22 English miles, and in length nearly 300 stadia, or about 42 English miles. One canal connected the lake with the Canopic arm of the Nile, and another with the old harbour of Alexandreia, the Portus Eunostus. [ALEXANDREIA] The shores of the Mareotis, were planted with olives and vineyards; the papyrus which lined its banks and those of the eight islets which studded its waters was celebrated for its fine quality; and around its margin stood the country-houses and gardens of the opulent Alexandrian merchants. Its creeks and quays were filled with Nile boats, and its export and import trade in the age of Strabo surpassed that of the most flourishing havens of Italy.
Under the later Caesars, and after Alexandreia was occupied by the Arabs, the canals which fed the lake were neglected, and its depth and compass were materially reduced. In the 16th century A.D. its waters had retired about 2 miles from the city walls; yet it still presented an ample sheet of water, and its banks were adorned with thriving date-plantations. The lake, however, continued to recede and to grow shallower; and, according to the French traveller Savary, who visited this district in 1777, its bed was then, for the most part, a sandy waste. In 1801 the English army in Aegypt, in order to annoy the French garrison in Alexandria, bored the narrow isthmus which separates the Birket-el-Marioutfrom the Lake of Madiehor Aboukir, and re-admitted the sea-water. About 450 square miles were thus converted into a salt-marsh. But subsequently Mehemet Ali repaired the isthmus, and again diverted the sea from the lake. It is now of very unequal depth. At its northern end, near Alexandreia, it is about 14 feet deep, at its opposite extremity not more than 3 or 4. Westward it forms a long and shallow lagoon, separated from the sea by a bar of sand, and running towards Libya nearly as far as the Tower of the Arabs. The lands surrounding the ancient Mareotis were designated as the Mareotic Nome (Μαρεώτης Νόμος, Ptol. 4.5. §§ 8, 34); but this was probably not one of the established Nomes of Pharaonic Aegypt.
[W.B.D]