"One U.S. President Believed The Hollow Earth Theory And Approved A Journey To The Center Of The Earth"

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That theory crossed John Quincy Adams’ desk thanks to an Army officer with political connections named John Cleves Symmes, Jr.

"Starting in 1818, Symmes had been re-popularizing the hoary notion that the Earth was hollow. What Symmes brought to the age-old Hollow Earth theory was the contention that there were openings thousands of miles wide at the Earth’s poles through which one could venture inside our planet"

The successor to John Q. Adams, General Andrew Jackson, cancelled the expedition saying "Everyone knows the Earth is Flat."