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Machu Picchu is probably one of the most famous ruins of old civilizations known in America. Was built around 1450 by the Inca Empire, it's located very close (80 km) to what today is the city of Cusco. It was abandoned around 100 years later when the Spanish arrived to America.
As the time passed, the jungle grew around it. It was hidden from tourists for long time until 1911 when an American explorer found it and started to make excavations. Of course! if you ask to the Germans they will say that a German explorer discovered it 50 years before. Anyway, It immediately became a protected place by the Unesco.
During the first years of excavations, bones and artifacts found in the ruins were sent to Yale University with the purpose of studying it. They were supposed to give it back 18 months later buuuut, they didn't really returned it until 2012 ... almost 100 years after
You can read more about Machu Pichu here.
