Jerusalem: Hezekiah's Water System

The main water supply for the city of Jerusalem was the spring of Gihon, which flowed out of a cave on the eastern side of the hill on which the city stood. The Hebrew word means "gushing out" and was given because the spring does not have a steady flow but bursts from the rock at various times each day. Before David captured Jerusalem about 1000 BC, the Jebusite inhabitants dug a shaft from the city into the cave. Thereafter, they were able to draw water from the pool below.

The entrance to the cave was outside Jerusalem's walls, in the Kidron Valley. This was a significant weakness in the city's defense because the water supply was exposed to enemies. In fact, it is possible that Joab, David's commander, entered the cave and climbed up the shaft to capture the city for David.

When King Hezekiah learned that the dreaded Assyrian army had arrived in Israel, he recognized the threat his exposed water supply posed for Jerusalem's survival. He dug a tunnel through the ridge on which the city was built, bringing water to the other side, and then covered up the cave's opening. (The walled part of Jerusalem was a lower elevation on the western side of the ridge, so the water could flow to a pool, the pool of Siloam, within the city walls.) To this day, this extraordinary accomplishment ranks as one of the engineering marvels of the ancient world.