Ngorongoro Crater (Tanzania). At 610m deep and 260 sq km, this is the largest unflooded caldera in the world. A blue-green vision from above it's a haven for engangered wildlife and Maasai livestock. The crater was formed three million years ago when a giant volcano, which could have been as high as Kilimanjaro, exploded and collapsed. The caldera formed the concentric fractures in the crust cracked down to a magma reservoir deep underground. (Photo by John Bryant/Getty Images)

Hucul horses play in the wild meadows and forests near Odrzychowa in southeastern Poland on October 18, 2014. Huculs, a primitive breed of horse, escaped total extinction due to the efforts of scientists and Polish farmers. (Photo by Janek Skarzynski/AFP Photo)

A man stands beside the Philippine flag as colorful umbrellas adorn a village hall in suburban San Juan, east of Manila, Philippines, on June 27, 2013. (Photo by Aaron Favila/Associated Press)

A cow grazes in a field in front of the Nahr Bin Omar oil field and facility near Iraq's southern port city of Basra, on April 4, 2023. (Photo by Hussein Faleh/AFP Photo)

Dancers perform during the closing ceremony of the 19th Asian Games at the Hangzhou Olympic Sports Centre Stadium on October 8, 2023 in Hangzhou, Zhejiang Province of China. (Photo by Tingshu Wang/Reuters)

Members of South Korean K-Pop girl group Brave Girls pose on the red carpet at KCON Seoul 2022 in Seoul on May 7, 2022. (Photo by Anthony Wallace/AFP Photo)

A healthcare worker dressed as Santa Claus distributes gifts to children at the Ayeyarwady Covid Centre in Mandalay, Myanmar, on December 25, 2020, Christmas Day, amid the Covid-19 pandemic, caused by the novel coronavirus. (Photo by Ye Aung Thu/AFP Photo)

Britain's Princess Elizabeth clasps her hands in sympathy as Sergeant Jean Bayliss faints at her feet during an inspection of the guard of honour of the Women's Royal Army Corps at Shrewsbury Castle, Shropshire, on July 6, 1949. (Photo by AP Photo)