Geography: Noah builds two very tall towers in strategically important localities. One tower is associated with Lehi-Nephi, and the second with Shilom. Each of the two lands under Noah's control have a very high tower built such that the land may be surveyed from the top of that tower. These are certainly defense systems from which a lookout may be maintained over the surrounding territory.
Verse 13 notes that the hill north of the land Shilom was a "resort for the children of Nephi at the time they fled out of the land." This is a reference to the departure of Mosiah from Nephi (see the chronicle beginning in Omni 1:12). Sorenson suggests that "resort" should be seen in the context of a staging point, and notes that "the Zeniffites likely inhabited only the local land of Nephi (and perhaps also Shilom), for the hill was convenient only to those two localities." (Sorenson, John L. The Geography of Book of Mormon Events: A Source Book. FARMS 1990, p. 239.)