Albert Barnes Commentary 2 Samuel 23:15

"And David longed, and said, Oh that one would give me water to drink of the well of Beth-lehem, which is by the gate!" — 2 Samuel 23:15 (ASV)

A cistern of deep, clear, cool water, located about three-quarters of a mile north of Bethlehem, is called David’s Well by the monks. It is possible the old well has been filled in since the town was supplied with water by the aqueduct.