Erich Lessing

Discovered in 1880 on the wall inside Hezekiah’s Tunnel, the Siloam Inscription describes the final moments in the tunnel’s excavation, when the two teams of tunnelers were near enough to each other to hear the picks of the opposite team through the rock. Both teams repeatedly changed directions toward the sound of the other and finally broke through: “Water [then] flowed from the spring to the pool,” the Siloam Inscription tells us. Expanding on the ideas of earlier explorers, geologist Dan Gill proposed in BAR over a decade ago that the tunnelers were simply following and enlarging a natural underground stream, or karst. Although widely accepted, Gill’s hypothesis failed to explain several features of Hezekiah’s Tunnel: Why, when the two teams of tunnelers were so near, did they have to struggle to find the other, as the Siloam Inscription and the changes in direction near the meeting point tell us? And why, if they were following an underground stream, did they dig several “false tunnels” in the wrong direction?