The Nazis Plot to Blow Up Hoover Dam

What do the Eiffel Tower and the Statue of Liberty have in common?

For millennia, Stonehenge has amazed and confounded visitors and archaeologists alike.  The massive awe-inspiring circle of stones was obviously important to its prehistoric builders.  But what is it for?  How did they build it?  And why?

Frédéric Auguste Bartholdi was on the cutting edge of a new construction technique while constructing the Statue of Liberty.

Ancient civilizations used advanced engineering techniques to access water for both health and luxury.