While we know that the golden plates were taken by the angel Moroni, whatever happened to the box that Joseph Smith found them in on the Hill Cumorah?
According to David Whitmer, Joseph Smith never retrieved the box from the hill. Instead, he kept the plates safe by hiding them in a hollow log near his house or other secure locations while he underwent the work of translation.
So, where is the box now?
Geroge W. Givens in Little-Known Facts in Mormon History writes:
Often ignored in LDS history is the fate of the stone box in which the golden plates were deposited on Hill Cumorah and to which Joseph was led in 1827. Once the plates were removed, neither the prophet nor anyone else appeared interested in the fate of the stone box itself.
Almost fifty years later David Whitmer was interviewed by a Chicago Times reporter who wrote that "three times has he [Whitmer] been at the hill Cumorah and seen the casket (box) that contained the tablets and the seer-stone. Eventually the casket had been washed down to the foot of the hill, bit it was to be seen when he last visited the historic place.
So the truth is, no one knows where this box is today, or if it's even still at the Hill Cumorah buried under debris. But it's one of those Church mysteries that gets you thinking, what if?