'Upper' in the Bible

Then Yahweh said to Isaiah, "Go out now to meet Ahaz, you, and Shearjashub your son, at the end of the conduit of the upper pool, on the highway of the fuller's field.

The king of Assyria sent Rabshakeh from Lachish to Jerusalem to king Hezekiah with a large army. He stood by the aqueduct from the upper pool in the fuller's field highway.