Note the modern railing on the staircase leading down into the Tunnel. There are some 30 shafts leading down into the tunnel. The tunnel is 26 to 75 feet below the surface.
This "aqueduct" is about 3 miles long and carries water from the Wadi Biyar springs to the Upper of the three of "Solomon's Pools." Along the way it passes through a deep rock cut trench that collects additional water from the aquifer. The trench is covered with stones and dirt—and thus is buried.