Fyn Baily aged eight at the Bloodstock festival on August 13, 2011 in Walton-on-Trent, United Kingdom. Bloodstock is the UK's largest heavy metal festival and features both established and unsigned bands over four days. (Photo by Bethany Clarke/Getty Images)

Ultra-Orthodox Jews inspect etrogs, or citrons, inside a shop in the Mea Shearim neighbourhood in Jerusalem, 07 October 2014, as they look to purchase an unblemished fruit ahead of the holiday of Sukkot. (Photo by Jim Hollander/EPA)

Located in the Mokattam Mountain in southeastern Cairo, Egypt, the Monastery of Saint Simon or the Cave Church is a beautiful and mystical location. The area is also known under the name of the “garbage city” because of the large population of garbage collectors or Zabbaleen that live here and who are the descendants of farmers who started migrating from Upper Egypt to Cairo in the 1940s.

A protester holds a sign in front of riot policemen during an anti-G20 demonstration through the streets of Nice on November 1, 2011 in Nice, France. Anti-G20 demonstrators are gathered in Nice ahead of the arrival of the world's top economic leaders for the G20 summit in Cannes on November 3rd and 4th. The leaders are expected to debate current issues surrounding the global financial system in the hope of fending off a global recession and finding an answer to the Eurozone crisis. (Photo by Christopher Furlong/Getty Images)

First class seat of Emirates Airbus A380 registration A6-EDP at Munich Airport Franz Joseph Strauss on November 25, 2011 in Munich, Germany. Emirates Airlines has launched a new daily A380 service from Dubai to Munich with its first flight. (Photo by Alexander Hassenstein/Getty Images)

The sea otter (Enhydra lutris) is a marine mammal native to the coasts of the northern and eastern North Pacific Ocean. Adult sea otters typically weigh between 14 and 45 kg (31 and 99 lb), making them the heaviest members of the weasel family, but among the smallest marine mammals. Unlike most marine mammals, the sea otter's primary form of insulation is an exceptionally thick coat of fur, the densest in the animal kingdom. Although it can walk on land, the sea otter lives mostly in the ocean.

“Sniff out the Appenzell Cheese”. Alexander Hunter, 30, of Greenwich, Conn., took this photo in Appenzell, Switzerland, in September 2014. (Photo by Alexander Hunter)