The two armies were apparently exhausted (see Ether 14:31) and probably remained in the land of Corihor recuperating (see Ether 15:1) during the time of the exchange of epistles. When fighting resumed, it carried them to "the waters of Ripliancum" (Ether 15:8). In what direction the armies marched is not said. The waters of Ripliancum was probably near the "eastern" seashore (see Ether 14:26). The definition given to Ripliancum --"large, or to exceed all" (Ether 15:8)-- implies that it was no ordinary body of water.
According to Warren and Palmer, the "waters of Ripliancum" could be the drainage of the River Papaloapan, which flows to the sea at Alvarado (Palmer, 1981). It is illustrated on Map #7-2. An ancient site located in the Papaloapan basin is called La Mojarra. It is about seventeen kilometers due south of the present city of Alvarado on the Acula River. A monument found there recently has calendar dates of May 21, A.D. 143 and July 13, A.D. 156 (Capitaine, 1988), which would correspond to the "land northward" of the Nephites, but it is very probable that there were much earlier occupations as well.
The interpretation of the large inland lagoon system called the Papaloapan basin as being Ripliancum is based on its nearness to the Gulf of Mexico Further, it was not called a sea, lake or river. Rather, it is large and undefined, being a place where today large ocean-going fishing boats ply the waters. It is also the distance of one-day's walk northward from the hill where it is postulated that the last Jaredite battle took place. In fact, it can be seen from the slopes of the Cerro Vigia (hill Ramah). [Bruce W. Warren and David A. Palmer, The Jaredite Saga, p. 7-7, 9-3, unpublished]
Ether 15:7 The waters of Ripliancum ([Illustration]): ERTS Satellite picture showing the Papaloapan lagoon system (Waters of Ripliancum?) in relationship to the Cerro Vigia (Hill Ramah/Cumorah) with two locational keys to the Mesoamerican map. [David A. Palmer, In Search of Cumorah, pp. 94-95]
Ether 15:7 The waters of Ripliancum ([Illustration]): The great swamp and lagoon system of central Veracruz would serve as the "waters of Ripliancum" that blocked the retreat of Jaredite armies. (Photo by James C. Christensen used by permission of The Church of Jesus Christ of Latter-day Saints.] [John L. Sorenson, An Ancient American Setting for the Book of Mormon, p. 347]