From the Made by one man Youtube Channel...
For decades, many have wondered and speculated at the Coral Castle down near Miami Florida built by one man.
Coral Castle is an oolite limestone structure created by the Latvian American eccentric Edward Leedskalnin (1887–1951) located in Leisure City, Florida, in Miami ...
This is the first video I've ever seen that seems to have a good idea on how it was constructed by one man.
One of the biggest mysteries is how Ed managed to make a hinge for a door from a single block of coral weighing tons, that could be opened by a 5 year old child pushing on it with a pinky finger.
Here is a Wikipedia link as well. https://en.wikipedia.org/wiki/Coral_Castle
Sounds like this guy should have been a friend of Nikola Tesla's...
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