John Clark argues that the Book of Mormon describes an "hourglass" geography.
John Clark, "A Key for Evaluating Nephite Geographies," Review of Books on the Book of Mormon 1, no. 1 (1989): 23–27
Reconstructing an Elemental Geography
During the days of Alma and General Moroni, Book of Mormon lands consisted of three sectors that could be considered Nephite, Lamanite, and former Jaredite. The depopulated Jaredite lands comprised the land northward; Nephite and Lamanite lands lay in the land southward. Nephite lands, known as the land of Zarahemla, were sandwiched between the ancient Jaredite lands to the north and the Lamanite land of Nephi to the south. A narrow neck of land divided the land northward and the land southward; thus, Book of Mormon lands were shaped like an hourglass (Fig. 1). The land southward was further divided into northern and southern sectors by a narrow strip of wilderness that ran from the east sea to the west sea. Nephites inhabited the lands north of this wilderness divide, and Lamanites controlled those to the south. As evident in Figure 1, Nephite lands were quadrilateral, having four sides and four corners. We could quickly establish the size and shape of Book of Mormon lands using simple geometry if we knew the length and direction of at least three of its four borders. And, if we could link at least one important locality in Lamanite and Jaredite lands to an established point in the Nephite land of Zarahemla, we would have the basic skeletal structure of Book of Mormon lands-and a key for evaluating competing Book of Mormon geographies.
An elemental framework of Book of Mormon geography can be reconstructed with just seven points or six transects (a line connecting two of these points), as shown in Figure 2. The following sections consider each transect shown in Figure 2 and present the data, inferences, and conjectures used to determine the distance between each pair of localities. As can be seen, the southern border of Nephite lands was considerably longer than its northern border; and the western border was much longer than the eastern border.
Before proceeding with the specifics of each transect, I need to clarify how I am treating distance and direction. I assume that the Nephite directional system was internally consistent and that this consistency persisted throughout the period of their history. I do not pretend to know how Nephite "north" relates to the north of today's compass, and such information is irrelevant for my present purpose of reconstructing an internal geography. I do assume, however, that regardless of what any "real" orientation may have been, Nephite north was 180 degrees from Nephite south, and both were 90 degrees off of east and west. The directional suffix "-ward" is here loosely interpreted to mean "in the general direction of." Thus, I read "northward" as "in a general northerly direction." Finally, all directions are directions from "somewhere." I assume the central reference point was the city of Zarahemla, located in the "center" of the land of Zarahemla (Helaman 1:24-27).
Distances in the Book of Mormon are more problematical than directions. My assessments of distance are based upon travel times, whether stated, inferred, or conjectured. Distance as "time" is familiar to most of us. When asked how far it is from Provo, Utah, to Burley, Idaho, for example, I quickly respond that it is "four hours" rather than 250 miles. If my dad is driving, the "distance" (in terms of time) is considerably less-and significantly more if my mother is driving. Similar concerns with velocity are relevant to Book of Mormon accounts. I have converted all travel times into "units of standard distance" (USD), analogous to our "miles" or "kilometers." The USD is based upon one day's normal travel over flat land. Travel through mountainous or hilly "wilderness" is considered to be half of the normal standard in terms of actual linear distance covered. In other words, two days of travel through the wilderness would cover the same as-a-crow-flies distance as one day's travel on a plain, this because of the extra vertical and lateral movement necessitated by more difficult terrain. Internal evidence in the Book of Mormon is convincing that "wilderness" refers to mountainous regions filled with wild beasts. Some Book of Mormon travel accounts involve the movement of men, women, children, animals, and food stores, while others concern armies in hot pursuit or blind retreat. For purposes of our USDs, travel of children and animals comes under the normal standard-being more susceptible to ground conditions or terrain. Army travel (war speed) is calculated at 150-200 percent of normal (or 1.5-2 times as fast). These estimates are proposed as close approximations that will allow us to reconstruct the relative length of each border of Nephite lands. My goal is to work within the limits of precision dictated by the text-all measures given here are merely approximate. I have not adjusted my estimates of distance to fit any preconceived notions of where these places may actually be. Such interplay between text and modern maps is inappropriate and results in forcing the text to fit one's notions or desires for placement of Book of Mormon lands. (It is no accident, for example, that most Church members in New York do not accept a limited area for Book of Mormon lands.)