Sechin Bajo

Sechin Bajo is an archaeological site located in the Casma Valley on the north-central coast of Peru. It sits near the better-known site of Cerro Sechín and the larger complex of Chanquillo in the wider Casma region.

Excavations at Sechin Bajo have revealed ceremonial architecture that is incredibly ancient, with radiocarbon dating placing its earliest construction phases around 3500 BCE to 3200 BCE. This makes it one of the oldest known man-made monumental ceremonial centers in the entire Americas.

Archaeologists have uncovered large platform mounds built using conical adobes, or mud bricks, alongside a sunken circular plaza. The site features evidence of multiple building phases, where later generations of the Casma Valley people built new structures directly on top of older, abandoned ones.

While the general area was known to locals for centuries, major excavations revealing the true age of the site were conducted in the 2000s by the German Archaeological Institute. The team, led by archaeologists like Peter Fuchs, uncovered the deeply buried circular plaza and platform mounds that dated back to the Preceramic period.