The Greeks were right in calling Susa "the ancient great city." Though it was not, as they imagined, at one time the abode of Memnon, the son of the morning, who had come to the help of the Trojans, we have made acquaintance with the ancient kingdom of Elam, the beginnings of which we had to place about the year 2500 B.C. We saw that the princes of this kingdom could make war upon Babylonia, and reduce it to dependence in the last centuries of the third millennium B.C., and that its armies must have reached Syria. Then Elam had withstood the Assyrians for a long time with very great stubbornness, until at length after brave struggles it succumbed to the arms of Assurbanipal. A relief in the palace of Assurbanipal exhibited Susa before its capture, in the year 645 B.C., stretching along between two rivers (the Shapur and the Dizful), and surrounded by high walls and numerous towers. The new Susa also, the Susa of Darius and his successors, extended, according to the evidence of Strabo, between the two rivers; according to his statement the city had a circuit of 120 stades, and according to Diodorus of 200 stades, _i.e._ of 15 or 20 miles--an extent which does not leave it far behind the fallen cities of the Assyrians, and Babylon.[435] But Susa, which in spite of its numerous population was inhabited only to a small extent by Persians, required to be fortified even less than Ecbatana. The royal citadel must keep the city in check, and afford the most complete security to the palace. We are expressly told that this citadel was protected by strong works, which would indeed be necessary for the position of affairs and the object of Darius.[436] According to the statement of Pliny, the citadel was surrounded by the Eulaeus, the name which he gives to the Choaspes; the Book of Daniel also represents the Ulai as flowing round the castle of Susa.[437] The ruins prove that the palace lay on the Shapur. Within the protecting walls of the fortress was the "golden dwelling," "the gold-adorned chambers of Darius" as Aeschylus calls them,[438] the "far-famed palace" in the language of Diodorus. According to Aelian Darius took a pride in the buildings which he had erected at Susa; it was he who had erected the famous works there.[439]