When Francisco Pizarro led 167 Spaniards in a conquest of the Inca state in 1532, the city of “Machu Picchu,” resting on a narrow ridge between two sharp peaks in a densely vegetated area of the Andes mountains, escaped detection. The rich, five-square-mile city, located 50 miles outside of the Inca capital of Cusco, Peru, would remain hidden in its high perch (nearly 8,000 feet above sea level) for 379 years.

It is believed that Machu Picchu was built sometime after 1438, a period of Inca expansion that witnessed the defeat of rival tribes in the region, and that the Incas abandoned the city shortly after the Spanish conquest. Unable to determine the Inca name for the city, researchers named it Machu Picchu (“old peak”) after the older mountain peak. Scholars also do not know the function of the city; containing temples, sacred plazas, garden terraces, and residences, it may have served as a fortress or as a retreat for the Inca royal family. Skilled as engineers, the Incas constructed a stone-paved road through forbidding terrain to connect Machu Picchu with Cusco.

Because the Incas did not develop a writing system, scholars have relied upon archaeological remains to learn about their civilization. In 1911, Hiram Bingham of Yale University discovered Machu Picchu nearly intact. One of only a few pre-Columbian urban centers found so well preserved, Machu Picchu is Peru’s leading tourist attraction.

PostScript: Though the Spanish invaders tried to eradicate the Inca empire, its customs have been preserved by the six million Quechua-speaking Indians remaining in the Peruvian highlands.