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 female army recruit attends a base training at the armored battalion in Setermoen, northern Norway on August 11, 2016. Norway has become the first NATO member to have compulsory conscription for women as well as men in the army. Recently, the first batch of army recruits joined the ranks in The Armored Battalion in the Norwegian Army located in Setermoen in northern Norway. (Photo by Kyrre Lien/AFP Photo)

Topless activist Kaila J. walks through the rain following a “Free the Nipple” demonstration in Hampton Beach, New Hampshire August 23, 2015. (Photo by Brian Snyder/Reuters)

The Boeing 747-8 cargo plane pilot has seen thunderstorms, shooting stars and sunsets from up above the clouds and has looked down on mountaintops, carpets of cloud and cities lit up at night. The incredible pictures give a glimpse of the view from the pilots are treated to every day. Here: Shooting stars over India. (Photo by Christiaan van Heijst/Caters News Agency)

A dressed reveler looks up to the famous cathedral in Cologne, Germany, Wednesday, November 11, 2015. Thousands of carnival supporters celebrate the traditional beginning of the carnival season in Germany. (Photo by Martin Meissner/AP Photo)

A hairdressing mannequin is seen outside a hair salon amid as Typhoon Matmo hits Nantong, Jiangsu province July 25, 2014. Matmo, which made landfall in Fujian Province on Wednesday, has brought strong winds and heavy downpours to more areas in China after it moved northward on Thursday, Xinhua News Agency reported. (Photo by Reuters/Stringer)

Participants run at the “Half-Naked Marathon” at Olympic Forest park in Beijing, China, February 28, 2016. This annual running event which requires participants to run half-naked, was organized to promote environmentally friendly lifestyles. (Photo by Kim Kyung-Hoon/Reuters)