A Tennessee man was mowing his lawn when we stumbled upon an eerie surprise.

After driving over some bumps, Ricky Green from Tullahoma examined his yard closer and found a rock sticking up through the ground.

After a little digging, he uncovered a wooden coffin.

It turns out, his yard contains an entire burial ground.

A Civil War historian confirmed that it is in fact an old cemetery, but it's history remains a mystery.