In this July 21, 2016 photo, a farmer walks a herd of sheep along the road leading from San Felipe Hidalgo toward the fireflies' forest habitat, near Nanacamilpa, Tlaxcala state, Mexico. Thousands of ... more 
In this July 21, 2016 photo, a farmer walks a herd of sheep along the road leading from San Felipe Hidalgo toward the fireflies' forest habitat, near Nanacamilpa, Tlaxcala state, Mexico. Thousands of tourists traverse the area's unpaved roads each weekend during the season, paying between 100 and 200 pesos ($5-$10) for a one-hour walk amidst thousands of fireflies.(AP Photo/Rebecca Blackwell) less 
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Associated Press | Photo By Rebecca Blackwell
Tue, Jul 26, 2016 6:57 PM EDT