Maya Calendar System

Timeline

1. c. -400–250El Mirador · PeténPreclassic sites show early astronomical alignments related to the 260-day and 365-day cycles, and the concept of the Long Count's starting point (the creation date) gradually took shape.
2. c. 250–900Copán · CopánClassic period inscriptions widely used Long Count dating; priest-astronomers computed eclipses, Venus cycles, and the Calendar Round, embedding the time system into dynastic political narratives.
3. c. 900–1200Chichén Itzá · YucatánAround the 11th century, calendar knowledge was preserved in codices; the Tzolk'in and Haab' continued to guide divination, sacrifice, and agricultural scheduling, closely tied to city-state political activity.
4. 1550Maya highlands · GuatemalaAfter colonial conquest interrupted the transmission of the official calendar, modern archaeology and epigraphy reconstructed the Maya time system from inscriptions and codices; some Maya communities still retain knowledge of traditional cycles.