And at the Mayan site Chichen Itza in Mexico ... into three-month seasons based on annual temperature cycles. By that calendar, spring starts on March 1, summer on June 1, fall on Sept.

There has been a lot of chatter in parts of the online world this week about the supposed discovery of a hidden complex of ...

And at the Mayan site Chichen Itza in Mexico ... into three-month seasons based on annual temperature cycles. By that calendar, spring starts on March 1, summer on June 1, fall on Sept.

And at the Mayan site Chichen Itza in Mexico, people gather during the equinox to watch the ... They break down the year into three-month seasons based on annual temperature cycles. By that calendar, ...