Some have proposed that after the destruction at the time of Christ's crucifixion, the face of the land was tremendously changed so that it would be impossible to correlate post-crucifixion maps and pre-crucifixion maps, thus rendering the study of Book of Mormon geography "useless." However, according to the Book of Mormon record itself, after the destruction the people "did build many cities again which were burned (4 Nephi 1:7), Zarahemla was rebuilt (4 Nephi 1:8), Ramah/Cumorah was still recognized and valued as a strategic hill (Ether 15:11; Mormon 6:4), the narrowneck and the narrow pass were still there (Mormon 3:5), the land northward and the land southward were still there (Mormon 3:5), the river Sidon was still there (Mormon 1:10). There were, however, "many cities which had been sunk (by water) that could not be renewed" (4 Nephi 1:9). Thus, according to the Book of Mormon record, although destruction might have been widespread, it apparently was only irreparable around coastlines or shorelines; and rightly so, for cities cannot easily be rebuilt upon water. I don't think there is a basis for saying that the geographical map was forever altered to the point of being unrecognizable. According to John Sorenson (The Geography of Book of Mormon Events: A Source Book, p. 298), the rapid rebound in population and prosperity confirms the general stability of the scene even after the destruction. [Alan C. Miner, Personal Notes]