Machu Picchu was built around 1450, at the height of the Inca Empire.[7] Its construction appears to date to the period of the two great Inca rulers, Pachacutec Inca Yupanqui(1438–71) and Túpac Inca Yupanqui (1472–93).[8] It was abandoned just over 100 years later, in 1572, as a belated result of theSpanish Conquest.[7][9] It is possible that most of its inhabitants died from smallpoxintroduced by travellers before the Spanishconquistadors arrived in the area.[10]Although it was located only about 80 kilometers (50 mi) from the Inca capital inCusco, the Spanish never found Machu Picchu and so did not plunder or destroy it, as they did many other sites.[11] The conquistadors had notes of a place calledPiccho, although no record of a Spanish visit exists. The types of sacred rocks defaced by the conquistadors in other locations are untouched at Machu Picchu.[9]