Often times the gate of an ancient city was located at a low point that was easily approached—via an incline ramp—from outside the city.
Note how there are outer and inner gate houses—with a courtyard between them. Also note how towers abound in the gate houses and associated structures. As a city was being defended, the courtyard between the two gate houses could be viewed as a killing field whereby defenders could shoot down from their towers and wound and/or kill the attackers with arrows and/or spears. Even if attackers were merely incapacitated, they would lie there bleeding and moaning and other attackers—in the deafening bloody chaos—would have to climb over their bodies in order to try to gain entrance to the city. Of course they themselves were vulnerable to same the fate as their “colleagues.” This must have had a detrimental effect on the second wave’s enthusiasm to attack the city!
In addition, as the attackers attempted to make their way through the inner gate, they would have to break down its outer door. They would then be confronted with another killing field between the six chambers (three on each side) of the inner gate. In this area, defenders could be positioned directly above the attackers—shooting arrows down on them.
As for “doors”—there does not seem to be too much physical evidence for how the gates were “sealed/closed.” However, we do know that in other structures that a pair of doors each swung on columns that could pivot in a socket. More on this, next post.
For some brief comments on the dating to the six–chamber gate at Megiddo Click Here. More on gates to follow.