Barren Wing Farm

An ancient wreck of some alien craft, a pale gray arc of hull or wing that pokes up over the crest of a hill, almost an acre of metal. When struck it has a tinny sound that doesn't echo and seems dull or dead.

Nothing grows on it. No grass, moss, nothing. Stuff built on it slides off or doesn't stay standing. There's a farmhouse adjacent to it, back a hundred feet. It's not a successful farm - an acre of land won't grow anything - but the owners do make a little money charging a copper for tourists to walk on and tap at the strange metal.