There are many things in the Book of Mormon that have been identified as anachronisms that are inconsistent with our current understanding of the time and the geography in which the Book of Mormon narrative is supposed to have taken place. Yet what's remarkable is that there are actually fewer anachronisms in the Book of Mormon now than when the book was first published.
Former Senator Robert F. Bennett, on page 216 of his book Leap of Faith, published in 2009, said the following:
"Picture a ledger sheet with the arguments of believers on the right side and of the critics on the left. Label it 1830.
"In 1830, all the external evidence was on the left side of the ledger, in favor of the critics. Writing on metal plates? Ridiculous; an obvious invention. Large cities in America, inhabited by the ancestors of the Indians? Nonsense; the Indians are nomadic tribesmen who live in tents…
"Think of the same ledger sheet, labeled 2009. Metal plates with writing on them, hidden in the ground for later generations to find? Joseph was right on that one; move it from the left side of the ledger to the right, as a mark in the book’s favor. Big cities among the Indians? Whether they were Nephite cities or not, there were clearly big cities with large populations in Meso-America before Columbus…Add to those items the others we have covered in the previous chapters that have come to light in just the last half century, and it is clear that the passage of time has put a good many new items on the right side of the ledger (in favor of the book) and removed some of the old ones on the left (against it).
"Such a trend is significant, because truth is the daughter of time. With most forgeries, the farther you get from its date of production, the clumsier it looks. In the case of the Book of Mormon, the farther we get from the date of its production, the better it looks. "