Science / Medicine : Ancient Water Tunnels Not Man-Made, Study Reveals

Ancient Jerusalem received its water through a system of underground passageways that brought water from the spring of Gihon to a storage reservoir inside the city. Archeologists have long believed that the system was man-made, but were puzzled by the circuitous routing of the tunnels, extraneous tunnels and other design “mistakes.”

New research that began with excavation of the waterworks in 1980 reveals that the system was based largely on a series of pre-existing fissures in the limestone and dolomite underlying the city, according to geologist Dan Gill of the Geological Survey of Israel.

Gill reported last week in the journal Science that many of the passageways were created naturally by dissolution of rock by rainwater long before the region was settled by humans. All the ancient technicians then had to do was dig appropriate connecting passages.

The discovery may also end a minor dispute about how David captured the Jebusite city of Jerusalem in about 1000 BC. The Bible suggests that he entered through the waterworks, but man-made waterworks did not exist then. Gill suggests that he entered through the naturally occurring passageways, which would have been known to “insiders” in the city.