Nephite fortifications consisted of two elements. The first was a mound of dirt, which placed the defenders above the attackers. Their projectiles would be aided by gravity. Second was the ditch or dry moat around the fortification. The effect of the ditch is not only to increase the height of the wall (and was probably the source of the dirt for the mound), but also to create difficult footing near the wall, thus requiring enemy soldiers to pay attention to their feet in addition to the target.
The archaeological site of Becán has a defensive system that combines parapet and ditch in the same combination. Archaeologists examined the possibility that the ditch was simply a by-product of building projects, but it shows signs that it was a conscious construction, not simply excavated so the dirt could be used elsewhere. Archaeologist Jeremy Sabloff reports: “Webster argues that given the local geology, the ditch would not have been an effective means of quarrying. Moreover, much more material was removed from the ditch than could have been used in any construction project at the site. Finally, materials from the ditch were piled up on the inside lip of [the] excavation to form an embankment but not on the outside lip, which would have been expected if the ditch had simply been a borrow pit.”