The official history tells us that North America was inhabited by stone age people who lacked the wheel, draft animals, or metal working. So ... moving a 91 ton stone block must have been challenging.
It sort of looks like the beginning of a pyramid being built, makes you wonder how they cut, transported and lifted those rock into place.
Moving the stones was probably easier then thought, because Wally Wallington (?) was able to move stones that weighed over 10 tons by himself with little difficulty.
“It’s a kind of magic”