The Maya developed the Long Count Calendar.
Notes on verification
Widely supported by encyclopedic and museum sources that the Maya developed and extensively used the Long Count calendar, but academic/archaeological evidence suggests earlier Olmec or Epi-Olmec origins, with the earliest inscriptions predating confirmed Maya use by centuries. The claim holds in the popular sense but omits this nuance.
Sources
- Drought May Have Spelled End for Maya | HISTORY (history.com)
- https://maya.nmai.si.edu/calendar/calendar-system (maya.nmai.si.edu)
- https://www.timeanddate.com/calendar/maya.html (timeanddate.com)
- https://kids.kiddle.co/Mesoamerican_Long_Count_calendar (kids.kiddle.co)