A reef shell lies on a beach as the sun sets on Lady Elliot Island located north-east of the town of Bundaberg in Queensland, Australia, June 10, 2015. UNESCO World Heritage delegates recently snorkelled on Australia’s Great Barrier Reef, thousands of coral reefs, which stretch over 2,000 km off the northeast coast. Surrounded by manta rays, dolphins and reef sharks, their mission was to check the health of the world's largest living ecosystem, which brings in billions of dollars a year in tourism. Some coral has been badly damaged and animal species, including dugong and large green turtles, are threatened. UNESCO will say on Wednesday whether it will place the reef on a list of endangered World Heritage sites, a move the Australian government wants to avoid at all costs, having lobbied hard overseas. Earlier this year, UNESCO said the reef's outlook was “poor”. (Photo by David Gray/Reuters)

Children sit under a crocodile based table, as they pose for photographers during a press preview of a themed auction that features the animal as artistic inspiration, entitled “Creatures Great and Small”, in London, Monday, December 15, 2014. The sale scheduled for December 17, 2014, explores animals across a diverse range of mediums and styles, from intricate carving details in 19th century furniture through to contemporary sculpture, according to Christie’s auction house. (Photo by Lefteris Pitarakis/AP Photo)

The Great Dismal Swamp is a marshy area in the Coastal Plain Region of southeastern Virginia and northeastern North Carolina, between Norfolk, Virginia, and Elizabeth City, North Carolina. It is located in parts of southern Virginia cities Chesapeake and Suffolk and northern North Carolina counties Gates, Pasquotank and Camden. It is a southern swamp, one of many along the Atlantic Ocean's coast, including the Everglades and Big Cypress Swamp in Florida, the Okefenokee Swamp in Georgia, the Congaree and Four Holes swamps of South Carolina, and some of the Carolina bays in the Carolinas and Georgia. Along the eastern edge runs the Dismal Swamp Canal, completed in 1805.

The Mexico – United States barrier – also known in the United States as the border fence, rotted fence or border wall – is actually several separation barriers designed to prevent illegal movement across the Mexico – United States border.

“The Eton wall game is a game similar to football and Rugby Union, that originated from and is still played at Eton College. It is played on a strip of ground 5 metres wide and 110 metres long next to a slightly curved brick wall, erected in 1717”. – Wikipedia

Photo: The “Collegers” and the “Oppidans” of Eton College take part in the “Wall Game” as boys in their traditional school uniform watch from on top of the wall on November 17, 2007 in Eton, near Windsor, Berkshire, England. The first recorded “Wall Game” took place in 1766 with competition between the two houses at the boarding school remaining as fierce as ever on the annual St. Andrew's day event. The object of the game is to get the ball to either end of the wall and score a goal, which has not happened since 1909. As well as scoring a goal the players can win points with a “shy”, where the ball is held against the wall and touched by the hand and awarded one point. (Photo by Christopher Furlong/Getty Images)

“The Berlin Wall (German: Berliner Mauer) was a barrier constructed by the German Democratic Republic (GDR, East Germany) starting on 13 August 1961, that completely cut off West Berlin from surrounding East Germany and from East Berlin. The barrier included guard towers placed along large concrete walls, which circumscribed a wide area (later known as the “death strip”) that contained anti-vehicle trenches, “fakir beds” and other defenses. The Soviet-dominated Eastern Bloc officially claimed that the wall was erected to protect its population from fascist elements conspiring to prevent the “will of the people” in building a socialist state in East Germany. However, in practice, the Wall served to prevent the massive emigration and defection that marked Germany and the communist Eastern Bloc during the post-World War II period”. – Wikipedia

Photo: West Berlin policemen and East German Volkspolizei face each other across the border in Berlin, circa 1955. (Photo by Three Lions/Hulton Archive/Getty Images)

Air conditioners, more than 500 in total, hang on the wall of an office building on August 15, 2011 in Fuzhou, Fujiang Province of China. This 25-story office building was built with no central air conditioner system, each office has it own individual unit installed on the exterior creating this wall of air conditioners. (Photo by ChinaFotoPress/Getty Images)