Drummers perform during rehearsals at the Bird's Nest National Stadium ahead of the IAAF Athletics World Championships in Beijing on August 20, 2015. The Athletics World Championships will be held at the stadium from August 22 to 30. (Photo by Greg Baker/AFP Photo)

“Super Enerji”. Taken on my road trip through Turkey. (Photo and caption by Michelle Brandemuehl/National Geographic Traveler Photo Contest)

ATTENTION! All pictures are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture.

“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)

Members of the Guard of Honor of the Presidential Regiment from Russia perform during the “Spasskaya Tower” international military music festival at Moscow's Red Square, Russia, September 10, 2015. The festival runs until 13 Sepember. (Photo by Maxim Shemetov/Reuters)

A girl performs martial arts during a function to mark International Women's Day at a school in Hyderabad, India, on March 7, 2014. (Photo by Mahesh Kumar A./Associated Press)

Jockeys spur buffalos during the Makepung buffalo races at Jembrana in Bali, Indonesia on October 23, 2016. Makepung is a tradition for farmers to celebrate a bumper harvest in Bali. (Photo by Kadek Raharja/Xinhua/Barcroft Images)

The crowd watches as stunt pilots Melissa Pemberton, Jurgis Kairys and Skip Stewart of The Immortals fly past pyrotechnics as they perform at The Australian International Airshow on March 1, 2015 in Avalon, Australia. (Photo by Scott E. Barbour/Getty Images)

Models smoke during a break at Sevilla de Boda (Seville Wedding) fashion show in the Andalusian capital of Seville November 27, 2015. (Photo by Marcelo del Pozo/Reuters)