President Nelson taught, "Good inspiration is based upon good information." If you are a Latter-day Saint and haven't read Oliver Cowdery's 8 essays on Church history, including Letter VII, you need to read them to understand Church history, the Book of Mormon, and the related teachings of the prophets.
Before the Smithsonian existed and began their mound investigations (and even during its beginning), there was Henry R. Schoolcraft. This illustration from Schoolcraft shows the remains of an ancient stone tower overlooking Moundsville, West Virginia and the Ohio River in the mid-1800s. There were several of these on both sides of the river and they are believed to have been used as observation and signal sites. If you look at the middle right side, the large Grave Creek Mound is shown.