But surely the point is there is NO evidence, only speculation supported only by further uncorroborated speculation that evidence would be found if we dug. There is a goblin down the well (speculation) Dig and you will find him...(supporting speculation). ;)
There was no evidence for the Palisades until a very observant person noticed marks on some aerial photos. That type of thing may be replicated elswhere but hidden by undergrowth.