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)

First graders attend a festive ceremony to mark the start of another school year in Slaviansk, September 1, 2014. September 1 marks the start of a new academic year for students in Ukraine. (Photo by Gleb Garanich/Reuters)

One part of “Celestrial Texts – Heavenly Tweets” by Laine Hogarty is seen as part of the “Hidden” annual sculpture exhibition at Rookwood Cemetery on September 15, 2014 in Sydney, Australia. Located in the suburb or Rookwood in Western Sydney Rookwood cemetery is the largest necropolis in the southern hemisphere. The Annual “Hidden” exhibition features works by local artists. (Photo by Mark Kolbe/Getty Images)

A couple walk on a catwalk in a flooded Saint Mark Square during a period of seasonal high water in Venice on October 29, 2018. Venice frequently floods when high winds push in water from the lagoon, but Monday's levels are exceptional and forecast to rise even higher, to 160 centimeters (nearly 63 inches) by mid-afternoon. (Photo by Manuel Silvestri/Reuters)

A tourist has her photo taken wearing a Santa hat on Christmas Day on Bondi Beach in Sydney, Australia on December 25, 2018. (Photo by Peter Parks/AFP Photo)

A grasshopper rests on a photographic camera during a meeting in the village of Alto Jamari called to face the threat of armed land grabbers invading the Uru-eu-wau-wau Indigenous Reservation near Campo Novo de Rondonia, Brazil on January 30, 2019. (Photo by Ueslei Marcelino/Reuters)

A woman carries a floral design handbag at the RHS Chelsea Flower Show in London, Britain on May 21, 2018. The annual show of floral art, timed to coincide with the RHS Chelsea Flower Show nearby, sees over sixty shops, restaurants and local businesses compete for prizes, with the awards given by RHS (Royal Horticultural Society) judges, this year on the theme of “Summer of Love”. (Photo by Toby Melville/Reuters)