It was probably during Alexander Jannæus' reign that the lower aqueduct was hewn, transporting water from the spring of Ein Eitam (near Bethlehem) to the vicinity of the Temple Mount. As Ein Eitam's altitude is only 30 meters higher than that of the mount, this was a significant feat of technology and engineering. The aqueduct had to bypass several ridges to reach its destination and is therefore very twisted, requiring it to maintain a slope of three feet for every mile.