A mysterious stone statue, possibly the portrait of the great Inca emperor Pachacuti, once stood in Machu Picchu, according to archival research.

Likely placed against a round stone wall on one of Machu Picchu's terraces, the statue had already disappeared by the time American explorer Hiram Bingham climbed the steep jungle slope to be faced with an archaeological wonder exactly a century ago on July 24, 1911.

Bingham, who has been credited as one possible inspiration for the "Indiana Jones" character, saw "a remarkably large and well-preserved abandoned city " perched some 8,000 feet in the clouds "in a wonderfully picturesque position," he wrote in the March 26, 1914, issue of Nature.

Surrounded on three sides by the gorges of the Urubamba River (also called the Vilcanota River), and tucked between two massive mountain peaks -- the Huayna Picchu and the Machu Picchu -- the vine-covered ruins of "the lost city of the Incas" were never really lost at all....