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 view of one of the dioramas contained inside iron boxes as part of the “S.A.C.R.E.D” installation by Chinese artist Ai Weiwei during a media preview at the cathedral in Cuenca, Spain, July 21, 2016. Ai Weiwei has reproduced scenes of his incarceration for a new art installation, a series of almost life-size dioramas – encased in steel boxes – showing his life in jail. (Photo by Susana Vera/Reuters)

Two Year ago, we featured some creative nail photography by Vlad Artazov, who used nails to create some lovely and moving scenarios. The story of Nail Art is still one of most popular post on our site. And today’s topic: The story of Pin is a kind of similar photography work by Jun.C, a professional portrait photographer. Not sure whether Jun’s work was inspired by Vlad Artazov, but that is definitely worth seeing still. Let us know which one you like better? Nail or Pin?

“I was born in 1977 in Warsaw, Poland. I had graduated from the High School of Art in Warsaw. My journey into the world of photography began in the early 90's, but at that time my biggest passion was painting. Painting helped me develop vision that was hard to create. Unfortunately I had to leave the paintbrush and canvas. A few years ago, I opened “the door” to my own world with help of a different key”... – Michal Karcz. Photo: “Last Outpost”. (Photo by Michal Karcz)

In this March 15, 2012 file photo, a Chinese woman poses for photos near a sculpture depicting a Chinese yuan note at an art district in Beijing, China. China devalued its tightly controlled currency on Tuesday, August 11,2015, following a slump in trade, triggering the yuan's biggest one-day decline in a decade. The central bank said the yuan's 1.3 percent fall was due to a change aimed at making its exchange rate controls more market-oriented. But any change raises the risk of tensions with China's trading partners. (Photo by Ng Han Guan/AP Photo)

This graceful husky appears to be smarter than your average dog having apparently mastered the art of walking on water. The soft-footed canine was photographed while making its way across a lake in northern Russia. Photographer Fox Grom captured a remarkable set of images after heavy rain fell on a frozen lake to create the amazing illusion. The 40-year-old, who works as an all-terrain vehicle driver, regularly walks his pet dogs, Alaska and Blizzard, near the natural beauty spot. “I always take pictures of my dogs whilst walking them but on this occasion there was an extraordinary phenomenon“, he said. “The ice was already very thick when it rained heavily making for a spectacular scene”. Here: Husky dog Alaska walks on water in Northern Russia, January 2015. (Photo by Fox Grom/Visual Press Agency)

Nguyen Manh Quan (top), 26, a civil servant, carries a girl using his throat area as he performs during a showcase of the traditional Thien Mon Dao kung fu at Du Xa Thuong village, southeast of Hanoi, Vietnam May 10, 2015. Thien Mon Dao, a traditional Vietnamese martial art, was formed by 18th century villagers in Du Xa Thuong village, who believed the art form could help improve health as well as fight against foreign invaders. There are currently about 3,000 practitioners including farmers, industry workers and state servants. These practitioners say they are able to bend metal against their bodies and carry heavy objects using their throats, eyes or tongues, as well as run across the surface of a river, according to Thien Mon Dao kung fu master Nguyen Khac Phan. (Photo by Reuters/Kham)

Members of the general public enjoy the “BEACH” at the National Building Museum August 25, 2015 in Washington, DC. The “BEACH” is an interactive architectural installation, with an “ocean” of nearly one million recyclable translucent plastic balls, that brings the experience of going to the beach indoor. (Photo by Alex Wong/Getty Images)