Here is a fellow who thinks that Burroughs' Pellucidar novels are historical truths, that the earth is hollow and somehow habitable and inhabited on the inside. In particular, he thinks Byrd the polar explorer was really exploring deep with the hollow earth:

A few years ago I spent a great deal of time researching the Arctic and Antarctic exploits of Rear Admiral Richard E. Byrd looking for anything that could explain why his name continues to pop up in any serious study of the Hollow Earth Theory.

 

I have already reported in my research about the possible involvement of the Admiral in the exploration of lands located inside our global world. The most significant fact is the lack of proof otherwise that really stands out in our investigation.

What a phrase he has found  in 'the lack of proof otherwise'! If you can't disprove to me whatever insane thing I just thought up--and bear in mind, I'm insane and therefore impervious to argument--it must be true!

Anyway, here is Byrd's  Snowcruiser, which is possibly worth seeing.

  


It was world famous in 1939, but quickly broke down in Antarctic conditions. Evidently the shifting ice fields periodically bury and expose it.