In his epistle to Moroni, Helaman states that "these are the cities which they [the Lamanites] possessed when I arrived at the city of Judea . . .The land of Manti, or the city of Manti, and the city of Zeezrom, and the city of Cumeni, and the city of Antiparah" (Alma 56:15,14)
According to John Sorenson, Manti itself seems likely to have been at the major ruin of La Libertad. It sits at the confluence of three large tributaries that form the Grijalva River just below the big archaeological site, and the required wilderness is immediately adjacent to the site. La Libertad was the largest city in the entire upper tributaries region of the Grijalva River (the proposed Sidon River) at about this time period. [John L. Sorenson An Ancient American Setting for the Book of Mormon, p. 259]
Alma 56:14 Manti (Illustration): John Sorenson's proposed site for the city of Manti (La Libertad). Topographic Map of the Pacific Coast of Chiapas and Guatemala. Map drawn by topographer Eduardo Martinez E. with the collaboration of Gonzalo Utrilla. New World Archaeological Foundation, Brigham Young University, 1982.