Alma 21:1

Now when Ammon and his brethren separated themselves in the borders of the land of the Lamanites, behold, Aaron took his journey towards the land which was called by the Lamanites, Jerusalem; calling it after the land of their fathers’ nativity; and it was away joining the borders of Mormon.

When Ammon and his brothers split up near the land of the Lamanites, Aaron traveled to a land called Jerusalem. The Lamanites named it after the land where their fathers were born. It was next to the land of Mormon.

When Ammon and his brothers split up in Lamanite territory, Aaron headed toward a city the Lamanites had named Jerusalem—after their ancestors’ homeland. It sat near the border of the land of Mormon.