Site of sacrifices: This ancient artwork depicts what human sacrifice might have been like during the hey day of the Inca culture.Courtesy Peru ArcheologicalJust in case you thought Mel Gibson’s movie Apocalytpo was a complete work of fiction, you might now want to reconsider. Researchers in Peru have uncovered the oldest-known Inca plaza, 5,500-year-old site was found in northern Peru.

Through carbon dating of items found at the site, researchers figure that plaza was in use between 3500 and 3000 B.C.

Much like today’s sites of spiritual gathering and rituals, the plaza was an impressive structure made of stone and adobe. It is circular in shape and sunken in to the ground of the Sechin Bajo archeological site in the Andes foothills about 200 miles northwest of Lima, Peru.

Next door, archaeologists also found a life size frieze depicting a sacrificer holding a knife in one hand and a human head in the other. That art piece as been dated as being about 3,600 years old.

All of the dating work on the Peru site gives further evidence that a very advanced society was bustling in the Americas at the same time that other urban cultures were thriving in Egypt and Mesopotamia.