The origins of Sechín, one of the country's oldest archaeological sites dating from around 1600 BC, remain a mystery. It's not clear what culture built this coastal temple, but the bas-relief carvings ringing the main temple, some up to 4 meters (13 feet) high, graphically depict triumphant warriors and their conquered, often beheaded enemies. The site was first excavated in 1937 by the archaeologist J.C. Tello. It has since suffered from looters and natural disasters.
Archaeologists are still excavating here, so access to the central plaza is not permitted. A trail leading up a neighboring hill provides good views of the temple complex and the surrounding valley. A small museum has a good collection of Chavín ceramics and a mummy that was found near Trujillo. To get to the ruins, head southeast from Casma along the Pan-American Highway for about 3 km (2 miles), turning east onto a paved road leading to Huaraz. The ruins sit about 2 km (1¼ miles) past the turnoff.