Tourists climb up and descend the steep stairs at the Pyramid of the Sun at the ancient archeological grounds of Teotihuacan Wednesday, July, 27, 2016, in Mexico. Teotihuacan is an ancient ... more 
Tourists climb up and descend the steep stairs at the Pyramid of the Sun at the ancient archeological grounds of Teotihuacan Wednesday, July, 27, 2016, in Mexico. Teotihuacan is an ancient Mesoamerican city located in a sub-valley of the Valley of Mexico. (AP Photo/Ross D. Franklin) less 
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Associated Press | Photo By Ross D. Franklin
Wed, Jul 27, 2016 8:18 PM EDT