In the 25th year the Lamanites apparently made a clean sweep of cities, "all of which were on the east borders by the seashore" (Alma 51:26). This initial Lamanite invasion was in the 25th year and is described in Alma 51:22-26. If the listing of cities invaded is in the correct chronological order from southward to northward, then we have the following:
North
Mulek
Gid
Omner
Morianton
Lehi
Nephihah
Moroni
South
Again, that sweep was apparently from the city of Moroni on the south to the city of Mulek on the north, with all the people apparently fleeing northward from the invading armies.
However, in Alma 59:5 we will learn that maybe all of the Nephites weren't swept northward because the people of Nephihah "were gathered together from the city of Moroni and the city of Lehi and the city of Morianton" and "were attacked by the Lamanites." Apparently, the people from the cities of Moroni, Lehi and Morianton had fled to be with the people of Nephihah at the time that their cities were initially attacked by the Lamanites.
From the listing above of cities, "all of which were on the east borders by the seashore," one might naturally understand why the people of the city of Moroni would want to flee (apparently northward) to the city of Nephihah. But why would the people from the cities of Lehi and Morianton want to flee (apparently southward) to Nephihah? The simple answer is that they wouldn't unless the city of Nephihah was not located on the coast. But if the city of Nephihah was not located on the coast, then where was it located?
Using simple logic, Nephihah's location would perhaps be not only near, but somewhat equally convenient to the areas of Moroni, Morianton, and Lehi; otherwise, why would they gather to Nephihah and not to another city. By locating Nephihah somewhat inland of the cities of Moroni, Lehi, and Morianton, we would satisfy all the criteria we have just discussed. Thus when Alma 51:26 says that "all of the cities" were "on the east borders by the seashore," I think we have to view the statement as being made from the perspective of the people in the local land of Zarahemla who were expanding their control into the east wilderness.
In Alma 50:14, it says that Nephihah was between the city of Moroni and the city of Aaron. The city of Aaron is conspicuously absent from the list of cities above which were ALL "on the east borders by the seashore" (Alma 51:26). The only other place in the Book of Mormon where we read about a city called Aaron is in relation to Alma's missionary journey in the land of Zarahemla. Alma left the city of Ammonihah and was going toward the city of Aaron (Alma 8:13-14). These places were all inland of the east coast; therefore, we have one more reason to place Nephihah in an inland position.
Now let us try to answer the question as to why the Lamanites hesitated to attack Nephihah. The possible answers that have been covered are:
(1) that it was inland (not on Amalickiah's desired coastal route);
(2) that it had been physically fortified; and
(3) the city center was heavily populated with fleeing Nephites from Moroni, Lehi, and Morianton.
All of these reasons are sound; in fact, the reader will notice in the account of the 31st year (Alma 62:18-26), that when the Nephites were trying to recapture the city of Nephihah, it was difficult for the Nephites to entice the Lamanites to come out of their fortified city and fight on the plains. Therefore, they used a stratagem of scaling the walls by night, which allowed them to take the city. In view of this difficulty, perhaps Amalickiah's primary strategy was to cut off critical supply lines from the coast, because it says "he kept [his Lamanite armies] down by the seashore, leaving men in every city to maintain and defend it. And thus (in that manner) he went on, taking possession of many cities," (Alma 51:25-26). [Alan C. Miner, Personal Notes]