Racks known as "tzompantli" were where the Aztecs displayed the severed heads of sacrifice victims on wooden poles pushed through the sides of the skull. The poles were suspended horizontally on vertical posts.

Eduardo Matos, an archaeologist at the National Institute of Anthropology and History, suggested the skull rack in Mexico City "was a show of might" by the Aztecs. Friends and even enemies were invited into the city, precisely to be cowed by the grisly display . . .