The curved concrete top of the tunnel grazes the dark-brown buzz cut of Lt. Col. Oshik Azulai, putting it 5 feet and 7 inches above the sand floor. The walls are about 30 inches apart — wide enough for two people to squeeze past each other, unless both are in body armor. It is cool in the tunnel, 46 feet under, and dark, of course. Cellphones do not work. MORE

Joan Rivers knew about the tunnels; Guess the secrets out now! MORE