The valley contains the small, once important town of Casma, which had to be rebuilt after being destroyed by the 1970 Ancash earthquake.

It is notable for the grand scale of numerous archaeological sites of the Casma/Sechin culture, including stone-faced pyramids and the Thirteen Towers of Chankillo.

(Coordinates 9°21′00″S 78°25′19″W / 9.35°S 78.422°W / -9.35; -78.422) The coastal pre-ceramic site of Huaynuná (Huaynuma), 13 km north of the Casma Valley, has also been investigated by archaeologists.

An early, public religious tradition of architecture is represented there by a large elevated structure built on a hillside.

Evidence from Huaynuná, as well as the dates from other Casma Valley sites, indicate that larger-scale irrigation agriculture, use of pottery, and weaving did not appear in the Casma Valley area until about 1600 BC, some 200 years later than similar developments on the central coast of Peru.