Beneath the Swedish capital lies an intricate web of underground train lines. More than 90 of the 100 stations in the 110km tunnel system, sometimes referred to as “the world’s longest art gallery”, have been decorated with paintings, installations, mosaics and sculptures by 150 artists since the 1950s. After spending a couple of weeks exploring arctic Norway and Sweden, London-based travel photographer Conor MacNeill headed underground to capture images of the metro stations. Here: A rainbow arcs over a girl on the platform of Stadion station. (Photo by Conor MacNeill/The Observer)

A visitor looks at a Morris Mini-Minor Car on display at the Victoria and Albert museums' new major exhibition, “British Design 1948-2012: Innovation In The Modern Age” on March 28, 2012 in London, England. This car, which was designed by Alec Issigonis, was the first one off the production line. The exhibition showcases some of the most iconic product design, fashion, furniture, graphics, architecture and fine art from the last 60 years, and opens to the public from March 31, 2012. (Photo by Dan Kitwood/Getty Images)

A series of Japanese good luck charms, called “Daruma”, are lined up ahead of the major national elections November 9, 2003 in Takasaki, Japan. The Daruma is said to bring exceptional good luck in all walks of life, but is used especially during election time by all candidates. People think that if they face a difficult situation, as symbolized by the doll that returns to its original position when knocked over, they will always bounce back. (Photo by Koichi Kamoshida/Getty Images)

Mirko Hanák was born in 1921 in Prague, Czech Republic and worked as a painter, graphic designer and illustrator. His specialties were animals and human figures that were full of life and fun. He also had a firm grasp on composition as his paintings were so well balanced despite his casual fluid line. He was working on “Charlotte's Web” the movie when he tragically died at the height of his career from leukemia in 1971.

Tattooist Jay Freestyle, who is based in Amsterdam, creates what only can be described as works of art that last forever on his clients' skin. His style is freehand – without any sketch or stencil and he inks the incredible drawings straight onto body parts. They might look expertly planned, but the swashes of colour, detailed line work and geometric shapes are all the result of some clever improvisation. Photo: An amazing example of his mixed style. (Photo by Jay Freestyle/360 Media Solutions)

Libyan rebel soldiers watch as they fire rockets (background) toward Libyan government troops near front-line positions April 6, 2011 outside of Brega, Libya. Rebel militias fighting against Libyan government loyalist soldiers continued their stand-off in the eastern Libyan desert today, regaining ground toward a key oil port while awaiting further NATO airstrikes in their quest to unseat longtime Libyan ruler Muammar Gaddafi. (Photo by Chris Hondros/Getty Images)