Ruins on Peru’s desert coast are 4,700 years old and suggest civilization in the Americas is far older than previously thought. “The site of Caral, in the Supe Valley north of Lima, covers 66 hectares (165 acres) and includes pyramids 21m (70ft) high arranged around a large plaza. Whether it can truly be seen as a civilisation comparable in attainment with contemporary Egypt and Mesopotamia is doubtful, but it demonstrates that the tradition culminating in the Inca Empire had deeper roots than anyone imagined.”