By doing the work in the mounds we find there are post molds left behind, and that will give us the size of the log and the size of the Bastions that stood in the earth banks. Post molds. Not only do you get that, but you also get carbon dating, and the dating goes from approximately 30 A.D. on the average to a high of 430 A.D. Right in the Book of Mormon timeline. That's how accurate the post-molds are for Ohio forts.