1: Dubai's Burj Khalifa is the tallest building in the world, but perhaps not for long. Saudi Arabia has announced plans to build a 1 kilometer (3,280 foot) tower into the sky, to be named the Jeddah Tower, scheduled for completion in 2020. The Burj Khallifa currently stands at 2,716 ft. (Photo by Matthias Seifert/Reuters)

Indian ivory furniture legs in the shape of a goddess from the first century AD are displayed in the 'Afghanistan Crossroads of the Ancient World' exhibition at The British Museum on March 1, 2011 in London, England. Displaying treasures that were in great danger during the years of civil war and Taliban rule, these surviving artifacts reveal Afghanistan's ancient culture, its fragility and its remarkable place in world history. The exhibition opens to the public on March 3 and runs until July 3, 2011. (Photo by Peter Macdiarmid/Getty Images). LONDON, ENGLAND – MARCH 01

Surfers surf at Surf Snowdonia in Conwy, North Wales, September 3, 2015. The surf park, which cost $22.8 million, opened on August 1 and is the world's first commercial artificial surfing lake, according to the company.The pool is 300 metres (980 ft) long and 110 metres (360 ft) wide, containing a total of six million gallons of water. A bi-directional snowplough-shaped wave-generation mechanism, towed on a cable between the two central towers, moves up and down the pool on a three-rail track, generating the waves. (Photo by Andrew Yates/Reuters)

Badminton School sixth form pupils (L-R) Lucy Warden, who got 3 A* and is off to study English at Durham, Sam Crumpton, who got 1 A* and 2 A's and is off to study to be a vet at Cambridge and Madeline Sunter, who got 2 A* and 1 B, and is off to study fashion at St. Martins, celebrate their A-level results on August 18, 2011 in Bristol, England. With another record year for A-level results, sixth-form students face a scramble for university places in the final year before tuition fees rise. According to the examination bodies the pass rate rose for the 29th successive year to hit 97.8 percent, while around one in 12 exams achieved the top A* grade. (Photo by Matt Cardy/Getty Images)

A Cambodian villager rides a buffalo during the Pchum Ben festival, the festival of death, at Vihear Suor village in Kandal province on October 1, 2016. Thousands of Cambodians descended on the small village northeast of the capital on October 1 to cheer on the annual water buffalo race that marks the end of the 15-day festival for the dead. (Photo by Chor Sokunthea/AFP Photo)

Actors, clowns and mime artists celebrate “Humor Day” in St Petersburg on April 1, 2022. April 1 is also referred to as “April Fool’s Day” and is a time for playing pranks in the country. (Photo by Anatoly Maltsev/European Press Photo Agency)

Revellers react after falling in the mud at Worthy Farm in Somerset during the Glastonbury Festival, Britain, June 26, 2016. (Photo by Stoyan Nenov/Reuters)

A demonstrator is detained during May Day rallies in Santiago May 1, 2013. (Photo by Ivan Alvarado/Reuters)