Uncovered tower of skulls reveals dark Aztec history

A tower made of human skulls has been unearthed in Mexico City. More than 650 skulls caked in lime were found near Templo Mayor one of the main temples in the former Aztec capital. Anthropologists believe the tower was part of a massive structure made of skulls that terrified the Spanish invaders according to contemporary accounts. Many of the skulls belonged to women and children who may have been part of religious rituals.