The exact location of the original fortress Acra, critical to understanding Hellenistic Jerusalem, had long been a matter of lengthy discussions. Historians and archaeologists had proposed various sites around Jerusalem, relying mainly on conclusions drawn from literary evidence. This approach began to change in the light of excavations which commenced in the late 1960s. New discoveries had prompted reassessments of the ancient literary sources, Jerusalem's geography and previously discovered artifacts. Yoram Tsafrir had interpreted a masonry joint in the southeastern corner of the Temple Mount platform as a clue to the Acra's possible position. During Benjamin Mazar's 1968 and 1978 excavations adjacent to the south wall of the Mount, features were uncovered which may have been connected with the Acra, including barrack-like rooms and a huge cistern. In 2015, the Israel Antiquities Authority announced the likely discovery of the Acra in a different location, south-west of the Temple Mount and north-west of the City of David.