The Mayans actu­ally had sev­eral cal­en­dars: a 52 “year” cal­en­dar round, bro­ken into 20 day / 13 “month”  seg­ments, a long-count cal­en­dar for trac­ing long peri­ods of time, a cal­en­dar for track­ing the phases of the moon, a cal­en­dar of the heli­a­cal cycle of Venus etc.  Your aver­age Mayan prob­a­bly mostly paid atten­tion to the [...] Read more »