The 150-square-metre Villa Ypsilon was designed by London- and Brussels-based firm LASSA, which is headed up by architects Theo Sarantoglou Lalis and Dora Sweijd.

Actress Emma Watson attends the World Premiere of Harry Potter and The Deathly Hallows – Part 2 at Trafalgar Square on July 7, 2011 in London, England. (Photo by Ian Gavan/Getty Images)

Rowan Atkinson attends the UK premiere of Johnny English Reborn at The Empire Leicester Square on October 2, 2011 in London, United Kingdom. (Photo by Dave Hogan/Getty Images)

Last weekend, the National Building Museum in Washington, D.C., opened a 10,000 square-foot ball pit to the general public, and everyone cheered that, finally, someone made their childhood dreams come true.

Actress Anne Hathaway attends the “The Dark Knight Rises” World Premiere at AMC Lincoln Square Theater on July 16, 2012 in New York City. (Photo by Jim Spellman)

Chinese artist Zhou Jie takes a nap on an unfinished iron wire bed, one of her sculpture works, after lunch at Beijing Now Art Gallery, in Beijing August 11, 2014. Zhou started her art project titled “36 Days” on August 9, in which she would live inside an exhibition hall with an unfinished iron wire bed, some iron wire sculptures in the shape of stuffed animal dolls, a certain amount of food and her mobile phone, for 36 days. The entire process is open to visitors and she may also interact with them, according to Zhou. (Photo by Jason Lee/Reuters)

Festival goer with phallus logo t-shirt during the Kanamara Matsuri Steel Phallus Festival at Kawasaki, Japan on April 2, 2017. The Kanamara Matsuri or Festival of the Steel Phallus is held on the first Sunday of April at the Kanayama shrine. The shrine celebrates a legend of a steel pen*s and was frequented by prostitutes who wished to pray for protection from sexually transmitted diseases. Visitors now wish for easy delivery, marriage and matrimonial harmony. Because of the large steel phallus the unusual festival has become a tourist attraction attracting many overseas visitors and is used to raise money for HIV charities. Phallus shaped candy, carved vegetables, decorations, and a big parade are all part of the festival. (Photo by DELETREE/SIPA Press/Rex Features/Shutterstock)

A heifer, tied with a rope, turns during “Toro de Cuerda” in the white village of Villaluenga del Rosario, southern Spain September 3, 2016. Dazzling clusters of cube-shaped houses perched on top of Andalusia's olive tree-studded mountains, the “Pueblos Blancos”, or white villages, of southern Spain are named for the lime wash the buildings are painted with to keep the interiors cool. The labyrinths of narrow alleyways are a throwback to when this region was known as Al-Andalus and was part of a medieval Muslim territory. While this region is stunningly beautiful and a big draw to tourists visiting the south of Spain, it is also one of the poorest areas in the country and has one of the highest unemployment rates in the European Union. (Photo by Marcelo del Pozo/Reuters)