Flourishing by A.D. 250-300, Maya civilization extended over large sections of modern Mexico and Guatemala, as well as Belize, and into present-day El Salvador and Honduras. The pre-Conquest inhabitants of this vast area left important clues to their understanding of religious and historical events in the remains of their architecture, painting, sculpture, distinctive polychrome ceramics, and sophisticated hieroglyphic writing. A vital key to understanding these clues is an appreciation of the solar, lunar, and planetary cycles that are woven through the Maya chronological records. The Maya...