In ancient times the Gihon Spring, located in the Kidron valley east of Jerusalem and outside the city wall, was the major source of water for the holy city. This circumstance made the city of David vulnerable to hostile attack. An opposing army could simply cut off the Hebrews’ water supply, and wait them out.
Accordingly, in the eighth century B.C., when Judah was threatened by the Assyrians, Hezekiah, king of Judah, cut an underground tunnel and diverted water from Gihon to the pool of Siloam inside the city. The record of this enterprise is found in the Old Testament (2 Kings 20:20; cf. 2 Chronicles 32:30).
This tunnel was explored by Edward Robinson when he arrived in Jerusalem in April of 1838. He made the first scientific study of this amazing engineering feat. The conduit, cut from solid rock in a rather circuitous route, was 1,750 feet long, with an average width of two feet, and an average height of six feet. Because the workmen’s chisel marks changed directions at about the halfway point, Robinson speculated that two crews had dug the tunnel, starting at opposite ends, finally meeting in the middle.
Some forty-two years later, his theory was confirmed.
In June of 1880, some school boys, playing in the cool waters of Siloam, wandered into the tunnel. One of them discovered strange markings on the wall about twenty feet in from the pool. The carvings were reported and, some months later, Professor A. H. Sayce came and sat for hours in the mud and water transcribing the inscription by candlelight.
The writing consisted of six lines of ancient Hebrew script which described the triumph of the ancient engineers’ remarkable feat in constructing the tunnel. The importance of this discovery may be summarized as follows.
- It revealed the phenomenal skill of those Hebrew engineers of more than 2,500 years ago. The conduit was not in a straight line, but in an intentionally designed S-shape which required precision skill by the workmen operating from opposite directions.
- The inscription stated that the tunnel was twelve hundred cubits in length, which indicates that the ancient cubit was approximately eighteen inches long.
- The discovery confirms the accuracy of the Old Testament record concerning the defensive maneuvers of Hezekiah against the Assyrian threat.
- The inscription is one of the oldest forms of classical Hebrew text in existence. This was the language in which the Old Testament Scriptures were originally composed.
We are thus grateful for this great discovery from the ancient past.