The great cliffs of Masada rise from the desert floor, nearly unapproachable except for a spur on the mount’s western side. Masada served as a palace/fortress for Herod the Great in the first century B.C. and then as a rebel stronghold during the Great Revolt against Rome that began in 66 A.D. The Romans were able to storm the fortress a few years later by building a ramp on the spur. But how much did the Romans have to add to the spur? The answer, provided in the accompanying article by author and geologist Dan Gill, overturns the conventional wisdom regarding the siege of Masada.