Completion is near on Monaco's tallest skyscraper ever, and its first new one since the 1980s. Fueled by a luxury-housing boom in the tax-haven nation, the Odeon Tower's so-called Sky Penthouse is expected to sell for more than any other apartment in the world has ever sold before. Photo: The five-story Sky Penthouse is expected to be complete in September 2015. The water slide extends from a dance floor in the residence down to a private infinity pool. (Photo by Tour Odeon)

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)

Felix Guirola, 52, rides a homemade bike with an advertising banner in Havana, Cuba, July 20, 2016. The handyman, who loves heights, provides advertising space for companies on homemade bikes that tower up to 7.5 meters (24.61 ft). He rides them around Havana in an ingenious way of getting around strict marketing regulations in the Communist-ruled island. (Photo by Alexandre Meneghini/Reuters)

Katie Francis, a member of the Difficult Access Team from Wiss, Janney, Elstner Associates, inspects a gargoyle while rapelling down one of the north tower on the west front of the National Cathedral while looking for damage from August's magnitude 5.8 earthquake and high winds from Hurricane Irene October 17, 2011 in Washington, DC. DAT members used cameras, cell phones and iPad computers to record places on the cathedral's west front where damage was apparent. (Photo by Chip Somodevilla/Getty Images)

(L-R) Pieter Van Lankveld, Jay Schippers, Ynze Oegema, Justin Kimmann, Teun Kivit and Twan Van Gendt compete during the Dutch National BMX Championships at Olympic Training Centre Papendal on October 11, 2020 in Arnhem, Netherlands. (Photo by Dean Mouhtaropoulos/Getty Images)

The Canary Wharf financial district stands in London, Britain on August 11, 2019. (Photo by Simon Dawson/Reuters)

A model showcases designs by Antonia Paris during the Women's RTW 3 catwalk during Rosemount Australian Fashion Week Spring/Summer 2011/12 at Overseas Passenger Terminal on May 5, 2011 in Sydney, Australia. (Photo by Stefan Gosatti/Getty Images)