Temple and theater 3,500 years older than Machu Picchu discovered in Peru (cnn.com)

This project just got started with a grant from Dumbarton Oaks in May and there aren't any papers, peer reviewed or otherwise, so take the dating with a grain of salt. It appears they're estimating the age based on the motifs carved in the temple walls until the carbon dating on some pigments comes back.

This is the professor in charge of the project: https://www.pucp.edu.pe/profesor/luis-muro-ynonan