If you’ve been lucky enough to travel to the “four corners” area of the southwestern United States (where U.S. states Utah, Colorado, Arizona, and New Mexico “meet”), then you may have seen or even visited some of the cliff dwellings built by ancient native Americans that were erroneously called Anasazi for thousands of years and now go by the term Ancestral Puebloans. Read on to find out what we know about how this ancient tribe of people kept time and why they needed to do so.