Herod's method was to erect huge retaining walls, fifteen feet thick, beyond the earlier ones. Between old walls and new, he stacked vaults, evening the surface with dirt and surmounting all with a platform. Because the new walls were so massive, the Temple enclosure could serve as a fortress, as it did during the revolt against Rome. In 70 AD, after conquering it, the Romans lost no time in battering down the parts that stood above the platform. They set their rams inside, slamming outward. On reaching floor-level they stopped. In the excavation near the southwest corner of the western wall, the archaeologists have left a section of a street undisturbed. Here we can see the stones of the upper courses lying where they fell when the Romans battered them down.

We do not know how the ancients managed to move these stones or set them so precisely. They had pulleys and levers, but 50 tons (not to mention 600!) is more than a modern construction crane can handle. Perhaps they arranged the work so that they never had to lift a stone: they began quarrying at the level of the building site, to which they built a ramp; oxen dragged the stone on the ramp, using rollers; after they had set the first course, they quarried from a higher point and raised the ramp. Yet this, no doubt, is easier said than done! Nor does it account for the remarkable precision.

Why did Herod use such enormous stones? First, because he wanted to achieve stability without cement. The Romans had developed a high-grade mortar, consisting half of lime. To get lime they had to burn limestone, and the fires required a great deal of wood. In Rome they preferred baked brick, which required even more wood. But wood they had aplenty there. Not so here. Trees were scarce. People developed the craft of building dry walls. According to an estimate by Ben-Dov, p. 89, if Herod had chosen to build these walls with smaller stones, using cement, he might have made it equally strong, but at the cost of a hundred square kilometers of forest. 

Herod had another reason, too, to use big stones. This western wall was a crucial factor in his hold on power. As king of the Jews, he had a great deal against him. He had usurped the power from the Hasmonean. He was a collaborator with Rome, and so his dominion seemed to contradict the Jewish covenant faith. His Jewishness was dubious: his mother was a Nabataean Arab, and his Edomite paternal grandfather had converted to Judaism under pressure. Herod had, in other words, a problem of legitimacy. He had to cow his subjects into submission. This wall was part of the cowing.

Josephus wrote: "... the city lay over against the temple in the manner of a theater" (Antiquities, XV 11.5). That is, by Herod's time most Jerusalemites lived on the western hill, which is higher than the Temple Mount and slopes down into the Cheesemakers' Valley. Whenever they looked toward the Temple, then, they would see the western wall -- and Herod's mighty stones. Ben Dov describes the effect:

"Even though in objective terms you might be standing at a point level with or even higher than the Temple Mount esplanade, the towering walls created the optical illusion that the Temple compound was higher still. The further you descended toward the street bordering the Temple Mount, the greater the sensation of its height: as you walked down, the mountain seemed to grow higher before you." (Ben-Dov, p. 78.)

Approaching, you would have made out more clearly the enormous size of the stones. Here the margins would have played their part, enabling you to distinguish them. Herod needed you to feel this awe. Every time you looked toward the Temple, he wanted you to sense his might and the might of Rome behind him -- and to connect all this with your God. Having no divine right, he tried to construct it in stone.

Mark 13:1-2

As He was going out of the temple, one of His disciples said to Him, "Teacher, behold what wonderful stones and what wonderful buildings!" And Jesus said to him, "Do you see these great buildings? Not one stone will be left upon another which will not be torn down."