It is hard to tell at what point the army of Moroni intercepted the army of Amalickiah, the text just says it was "in the wilderness" (Alma 46:31). However, if the remainder of Amalickiah's army were "taken back into the land of Zarahemla" (Alma 46:33), and if the phrase "land of Zarahemla" means the general land of Zarahemla rather than the local land of Zarahemla, then the interception point was probably beyond the land of Manti within the "narrow strip of wilderness" which ran round by the head of the river Sidon (Alma 22:27). [Alan C. Miner, Personal Notes] [See Geographical Theory Maps]
Geographical Theory Map: Alma 46:29-33 Moroni Overtakes Amalickiah in the Wilderness (19th Year)