Clearly bats, but entertaining so: the people who believe that another civilization exists under the surface of the earth, usually reached by holes at one or the other of the poles. It has a long if not exactly glorious history, including the Astronomer Royal Edmond Halley (the comet guy). One modern proponent is a Rodney M. Cluff, who put his money where his mouth is:
So convinced was Cluff that, in 1981, he flew his wife and five children from New Mexico to a new life in Alaska. “I thought, ‘Why don’t we see if we can find the way to the Hollow Earth?’
And was his wife keen? “She wanted to go back home. She thought I was crazy. But we did it anyway.”
In Alaska, Cluff met a small group of people who had travelled to the icy state with the same idea. Soon they were ready to embark upon their mission. “We started on the road up to Point Barrow,” he says. “We saw a sign, at one point, saying ‘This Is A Private Road: Don’t Go Any Further’. So we didn’t go any further.”
How long did he drive before he reached the sign and aborted the mission? “About an hour,” he says. There’s a silence while I process this information. “Less than…” Soon afterwards, the Cluff family moved back south.