Birtha (Mesopotamia) bastions are quite traceable. There are the ruins of a vaulted secret staircase, leading down from the heart of the citadel to the water's edge. Birtha (Mesopotamia) Birtha () was an ancient fortress on the river Tigris, which was said to have been built by Alexander the Great. It would seem, from the description of Ammianus, to have resembled a modern fortification, flanked by bastions, and with its approaches defended by out-works. Shapur II here closed his campaign in 360, and was compelled to retire with considerable loss. D'Anville and Edward Gibbon both identify Birtha as modern-day Tikrit, Iraq. The
History of Mesopotamia 2230–2050 BC according to the Short Chronology. Around 2334 BC, Sargon became ruler of Akkad in northern Mesopotamia. He proceeded to conquer an area stretching from the Persian Gulf into modern-day Syria. The Akkadians were a Semitic people and the Akkadian language came into widespread use as the lingua franca during this period, but literacy remained in the Sumerian language. The Akkadians further developed the Sumerian irrigation system with the incorporation of large weirs and diversion dams into the design to facilitate the reservoirs and canals required to transport water vast distances. The dynasty continued until around c. 2154 BC,