Coriantum "did build many mighty cities" (Ether 9:23). According to Verneil Simmons, there might be evidence which link Old World building techniques with that of the New World. In a lecture given at the Anthropology Museum in Mexico City, Simmons heard Dr. Ignacio Bernal report on the early site of San Jose Mogote in the Oaxaca Valley. He made reference to the odd bricks uncovered in the lowest level of that very early site (1500 - 1300 B.C.) -- flat on one side and arched on the other. He noted, with some surprise, that only in a few early sites in the Old World area of Mesopotamia had such convex bricks been found. Bricks formed with one flat side and a rounded or convex top are very impractical as building blocks and such bricks were quickly abandoned in both cultural areas. They seem an unlikely object for independent invention. [Verneil Simmons, Peoples, Places and Prophecies, p. 276]
Coriantumr and His People Did Build Many Mighty Cities
Although the text does not specify the size or population of the "many mighty cities" (Ether 9:23) built by Coriantum, the Book of Mormon reader would expect to eventually find some evidence for cities during the time period of the Jaredites. According to Daniel Peterson, within only the past few years, excavators have unearthed what is now termed the oldest city in North America, an Olmec center in Mexico called Teopantecuanitlan ("The Place of the Jaguars' Temple"). This site, which appears to have been inhabited from at least 1500 B.C. to 600 B.C., and which may indeed date back to 2000 B.C., covers an area of 241.5 acres and probably served as the residence for approximately 15,000 people. (This was a sizeable population for the period, almost anywhere.) The homes of the city's people line the local river banks. Two stone irrigation canals, each half a mile long and five feet deep, tell of a rather highly developed agricultural life at Teopantecuanitlan. [Daniel C. Peterson, Book Review in Review of Books on the Book of Mormon, Vol. 2, 1990, p. 46]