Machu Picchu is called the Lost city of the Incas. But now, there is a debate about who discovered this place, when and how. This an interesting multimedia from the New York Times.
The Lost City of the Incas
Debate rages in Perú: Was a Lost City ever lost?
http://www.nytimes.com/slideshow/2008/12/08/world/americas/20081208PERU_13.html
http://www.nytimes.com/2008/12/08/world/americas/08peru.html
