People hold out money as butchers sell their remaining produce of the year at discounted prices during the traditional Christmas Eve auction at Smithfield's market in London December 24, 2015. (Photo by Neil Hall/Reuters)

Kiyomura Co's President Kiyoshi Kimura (C), who runs a chain of sushi restaurants Sushi Zanmai, poses with a 212 kg (467 lbs) bluefin tuna at his sushi restaurant outside Tsukiji fish market in Tokyo, Japan, January 5, 2017. Kimura won the bid for the tuna caught off Oma, Aomori prefecture, northern Japan, with a 74 million yen (633,000 USD) at the fish market's first tuna auction this year. (Photo by Issei Kato/Reuters)

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.

Measuring just five feet at its widest point, the ultra-thin home was unveiled in the Polish capital of Warsaw on Sunday, October 21, 2012. Photo: The Keret House is squeezed into the space between two apartment buildings in Warsaw. There's a four-inch gap between the apartment buildings to either side. A perforated steel facade was used to allow in more light. (Photo by Andrea Meichsner/The New York Times)

A picture rotated 180 degrees shows visitors walking inside an “Upside-down House” attraction at the VVTs the All-Russia Exhibition Center in Moscow, on January 14, 2014. The attraction to experience a new perspective of a house standing upside down was opened first time in Russia, the show organisers said. (Photo by Alexander Nemenov/AFP Photo)

Urban photographer Roman Robroek spent five years scouring the continent for the grandest examples of forgotten architectural beauty. Here: Watch your step on this Polish spiral staircase. (Photo by Roman Robroek/South West News Service)

A woman carries a bag with a baby while being evacuated by local emergencies ministry members in Donetsk, Ukraine, February 2, 2017. (Photo by Alexander Ermochenko/Reuters)

Rescuers work at the accident scene on a bridge on July 24, 2011 in Wenzhou, Zhejiang Province of China. The train from Hangzhou to the city of Wenzhou derailed on a bridge that is 10 m above the field in Shuangyu Town of Wenzhou city at 8:34 p.m on Saturday. The first four coaches and the 15th and 16th coaches of the train went off the line killed 32 and injured 191 people. (Photo by ChinaFotoPress/Getty Images)