Travelers who have an interest in archeology and ancient cultures might want to add a trip to Arizona’s Coconino National Forest to their bucket lists.
The site is already known for its astonishing collection of petroglyphs, but it is now also becoming known for its ancient clocks and calendars, according to the BBC.
In 2005, Kenneth Zoll, a local volunteer, noticed that stones protruding from the massive rocks that bear the petroglyphs cast interesting shadows at certain times of the day. Wondering if the stones might be some type of calendar, he approached an archeologist who worked for the park service. He was told to watch the stones for a year and report back.
During that year, Zoll carefully observed the stones and made several amazing discoveries. For instance, on June 21, the summer solstice, the stones cast shadows on six specific images on the rocks. On December 21, the winter solstice, the sun lined up with a notch that was carved between two stones.
After studying the stones, Zoll believes they were created by the Sinagua people, who left the area in the 15th century. They were likely used to mark religious events and keep track of important crop growing seasons. Similar rock calendars have been found in various archaeological sites around the world, including in Mexico and Malta.
Over the years, Zoll has identified dozens of other ancient calendars throughout Arizona’s Verde Valley and now offers popular tours of the sites.