'Fountain gate' in the Bible

Then I went on to the fountain gate and to the king's pool: but there was no place for the beast that was under me to pass.

And the fountain gate repaired Shallun the son of Colhozeh, the ruler of the district of Mizpah; he built it, and covered it, and set up the doors thereof, the bolts thereof, and the bars thereof, and the wall of the pool of Shelah by the king's garden, even unto the stairs that go down from the city of David.

And by the fountain gate, and straight before them, they went up by the stairs of the city of David, at the ascent of the wall, above the house of David, even unto the water gate eastward.