North Korean soldiers march during a military parade marking the 105th birth anniversary of the country's founding father Kim Il Sung in Pyongyang, North Korea, April 15, 2017. (Photo by Damir Sagolj/Reuters)

A young visitor interacts with a baby hippopotamus swimming in its enclosure at the Berlin Zoo on January 1, 2018. Tourists and locals flocked to the zoo in the German capital on the unseasonably warm first day of the year. (Photo by Odd Andersen/AFP Photo)

An unidentified elderly woman, who was knocked over during the melee after a shot was fired in the direction of President Ford, is comforted by a passerby in San Francisco, September 23, 1975. (Photo by AP Photo)

The Clavie, a burning barrel packed with tar soaked sticks fixed on the top of a pole, is surrounded by people at the Doorie Hill on January 11, 2018 in Burghead, Scotland. People welcome in the New Year with the fire ceremony which has ancient roots dating back to the 1750s, when the Julian calendar was reformed in Britain. It is believed to bring good luck for the coming year. (Photo by Jeff J. Mitchell/Getty Images)

Sally Rand dances on a beach in St. Petersburg, Florida, February 17, 1936. (Photo by AP Photo)

British troops covered in flames from a petrol bomb thrown during a violent protest by job seekers, who say they were promised employment in the security services, in the southern Iraq city of Basra, March 22, 2004. (Photo by Atef Hassan/Reuters)

Chileans watch the sky with special suits prior to a total solar eclipse on July 2, 2019 in Paiguano, Chile. Around 25,0000 tourists arrived to Paiguano, a small town of around 1,000 inhabitants in the Elqui Valley, 650 km away Santiago. This is the only Earth's total solar eclipse of 2019 and the first one since 2017. From this point, the sun will fully disappear for around two minutes. It is best visible from a stripe in the South Pacific, Chile and Argentina. (Photo by Marcelo Hernandez/Getty Images)

At 10,582 square kilometres, the Bolivian salt flats – otherwise known as Salar de Uyuni – are the largest on the planet and contain between 50 and 70% of the world’s lithium reserves. After exploring Chile and Argentina, photographer Joel Santos decided to travel to Bolivia in January 2017 to check the salt flats off his bucket list. With an electrical storm rolling in, Joel and his two travelling companions were the only souls left on the vast flats and captured the eerie flats without a person in sight. (Photo by Joel Santos/Barcroft Images)