[Stone Wall picture from LDS Guide to Mesoamerica by Daniel Johnson, Jared Cooper, Derek Gasser, Cedar Fort, 2008, p. 155]
There are disagreements among theorists regarding what cities, city walls, and like structures were made of. Of course Mesotheorists enjoin the idea that their “hewn stone” structures graced Book of Mormon lands. The expression “hewn stone” is found in the Book of Mormon:
The bricks are fallen down, but we will build with HEWN STONES; the sycamores are cut down, but we will change them into cedars. (2 Nephi 9:10)
Unfortunately, such a descriptor was never used to describe any structure on Book of Mormon lands; it was a reference from Isaiah. There is however a single “stone” reference regarding border walls:
Yea, he had been strengthening the armies of the Nephites, and erecting small forts, or places of resort; throwing up BANKS OF EARTH ROUND ABOUT TO ENCLOSE his armies and also building WALLS OF STONE TO ENCIRCLE them about round about their cities and the BORDERS of their lands yea, all round about the land. (Alma 48:8)
This is the sole reference to “walls of stone” and is distinguished from “banks of earth” by being used merely as a “borders of their lands” and not to “enclose armies.” The difference was, “banks of earth” protected people, and the “walls of stone” identified “borders” just as property owners do today. The statement given by Alma was in regards to the Land Southward, not the Land Northward.
At the coming of Jesus, the earth quaked so hard that:
exceedingly great quaking of the whole earth…And many great and notable cities were sunk, and many were burned, and many were shaken till the buildings thereof had fallen to the earth, and the inhabitants thereof were slain, and the places were left desolate. (3 Nephi 8:12,14)
Since the quaking destruction occurred after these structures were made, we must conclude that they were obliterated and unless rebuilt, were left desolated and any walls made of rock or houses of cement were destroyed.
Conclusion: the hewn stone structures in Mesoamerica (or South America) are not Book of Mormon.
[See also Fortifications]