Birket Israel (trans. Pool of Israel) also Birket Israil or Birket Isra'in,[1] abbreviated from Birket Beni Israìl (trans. Pool of the Children of Israel) was a public cistern located on the north-eastern corner of the Temple Mount, in Jerusalem. The structure is believed to have been built by the Romans for use as a water reservoir and also to protect the northern wall of the Temple Mount. Arab locals have known it by this name since at least 1857.[2]

Some archaeologists have determined that the cistern was possibly built during the Herodian period to improve Jerusalem's water supply.[4] Others estimate the date of construction later, in around 130 CE. This view is held by Charles Warren who recorded that although some kind of fosse must have existed at the spot at a very early period, since there is no description of the pool in the works of Josephus, "and it is very improbable that he would have omitted to mention so enormous a reservoir had it existed in his time", it was most probably constructed by Roman emperor Hadrian during his restoration of Jerusalem. 

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