“The Darwin Beer Can Regatta is an event which has been held annually since 1974 in Darwin, Northern Territory, Australia at Mindil Beach. Participants create boats using empty beer cans, soft drink (soda) cans, soft drink bottle and milk cartons. The vessels are not tested for seaworthiness, prior to water events, and those that fall apart are part of the day's entertainment. A great many sundry events go along with the regatta, including concerts, a thong-throwing contest and the "Henley-on-Mindil" competition (named after the Henley-on-Todd Regatta), where participants run their "boats" around like Flintstones cars”. – Wikipedia

Photo: A Darwin Beer Can Boat sails in Darling Harbour on October 31, in Sydney, Australia. Darwin has been named as one of Lonely Planet's top ten cities in the world to visit in it's Best in Travel publication. (Photo by Mark Kolbe/Getty Images for Tourism NT)

A new 3D IMAX screen is installed at IMAX Darling Harbour on February 9, 2012 in Sydney, Australia. The new 3D screen at 29.5 metres by 35.7 metres will replace the former screen at IMAX Darling Harbour as the largest in the world. (Photo by Matt King/Getty Images)

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)

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)

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.

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)