In this February 19, 2014 photo, a skate seller puts slices of skate into styrofoam boxes for shipment to customers around South Korea at a fish market in Mokpo, a port city on the southwestern tip of the Korean Peninsula. The aroma of one of southwestern South Korea's most popular delicacies regularly gets compared to rotting garbage and filthy bathrooms. And that's by fans. The unusual dish is typically made by taking dozens of fresh skate, a cartilage-rich fish that looks like a stingray, stacking them up in a walk-in refrigerator and waiting. Up to a month in some cases. (Photo by Ahn Young-joon/AP Photo)

The Zhangjiajie National Forest Park is a unique national forest park located in Zhangjiajie City in northern Hunan Province in the People's Republic of China. It is one of several national parks within the Wulingyuan Scenic Area.

Female North Korean soldiers parade to mark the 60th anniversary of the signing of a truce in the 1950-1953 Korean War at Kim Il-sung Square, in Pyongyang. (Photo by Jason Lee/Reuters)

A military instructor helps a boy to shoot a rifle with blanks at a weapon exhibition during a military show in St.Petersburg, Russia, Sunday, January 17, 2016. (Photo by Dmitry Lovetsky/AP Photo)

Machu Picchu, Peru. A llama’s-eye view of the legendary Inca settlement at Machu Picchu, isolated high in the Peruvian Andes. (Photo by Jim Turner/National Geographic)

Soldiers of China's People's Liberation Army (PLA) jump as part of their winter training in temperature of negative 26 degrees Celsius at China's border with Russia in Heihe, Heilongjiang province, December 14, 2015. (Photo by Reuters/Stringer)

Ultra Orthodox Jewish men watch a bonfire during the Jewish holiday of Lag Ba-Omer in Jerusalem's Mea Shearim neighbourhood April 27, 2013. Israelis celebrate the Jewish holiday of Lag Ba-Omer, which marks the end of a plague in the Middle Ages that killed thousands of disciples of a revered rabbi in the holy land, by lighting bonfires across the country. (Photo by Ronen Zvulun/Reuters)

US marines watch the mushroom cloud from an atomic explosion rise above the Yucca flats, Nevada during a US nuclear weapons test. (Photo by Keystone/Getty Images). USA, 1945