The city of Aaron is named twice, in passages that may not refer to the same place. It first appears as the destination Alma2 set out for after the people of Ammonihah cast him out: he departed and took his journey toward the city called Aaron. On the way, weighed down with sorrow over the wickedness of Ammonihah, he was met by an angel who commanded him to return to Ammonihah and preach again (Alma 8:13-16). Amulek became his companion there.
A city of Aaron appears again around 72 B.C., when the Nephites laid the foundation of Nephihah between the city of Moroni and the city of Aaron, joining the borders of Aaron and Moroni; Moroni stood by the east sea (Alma 50:14). This places Aaron near Moroni and Nephihah toward the eastern seashore, whereas Alma’s intended Aaron lay near Ammonihah in the west. The record gives no description of the city of Aaron’s location, size, or extent, and does not say whether the two references name one centrally placed city or two distinct cities of the same name.