All north of this belt of wilderness was considered the land of Zarahemla; all south of it was included in the land of Nephi. We are nowhere told its exact breadth, and can only judge thereof from casual references in the narrative of the Book of Mormon.
The river Sidon flowed through the centre of the Nephite civilization of the days of the republic. After the convulsions that attended the crucifixion of the Holy Messiah, the physical and political geography of the continent was greatly changed, and the new conditions are very vaguely defined by the inspired historians.
On the western bank of the river Sidon was built the city of Zarahemla. From the time of its first occupancy by the Nephites, to the date of its destruction by fire at the crucifixion, it was the capital or chief city of the nation, the centre of its commercial activities, and the seat of government. It was the largest and oldest city within their borders, having been founded by the people of Zarahemla before the exodus of the Nephites, under the first Mosiah, from the land of Nephi.
When the Nephites, by reason of increasing numbers, the exigencies of war, or for other causes founded new cities the cities so built were generally called after the name of the leader of the colony or of some illustrious citizen, and the land immediately surrounding, contiguous or tributary to the new city was called by the same name. As an example we will take the city or land of Ammonihah, regarding which it is written: Now it was the custom of the people of Nephi to call their lands and their cities, and their villages, yea, even all their small villages, after the name of him who first possessed them; and thus it was with the land of Ammonihah.
Some of these lands appear to have been relatively small, more resembling a county, or possibly a township, than any other division at present prevailing in this country. Such we suppose to have been the lands of Helam and Morianton. Others, such as the lands of Bountiful and Desolation, embraced wide, extended tracts of country.
The exact place where Lehi and his little colony first landed on this continent is not stated in the Book of Mormon: but it is generally believed among the Latter-day Saints to have been on the coast of Chili in thirty degrees south latitude. In fact, the Prophet Joseph Smith so stated.