Inside the Afar Triangle in Ethiopia’s Danakil desert, camel caravans are used to carry salt. For centuries, the essential mineral has been mined by the Afar people, known for their ability to withstand extremes. The terrain is rugged, travelers are scarce and so are motor vehicles, where the average annual temperature is the highest in the world, and can rise to 122 degrees Fahrenheit, 50 degrees Celsius. (Photo by Ziv Koren/Polaris)

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.

Katjinga, a Rhodesian ridgeback dog who lives on a 20-acre farm in Germany, adopted an abandoned pot-bellied piglet in August 2009. The tiny black piglet, named Paulinchen, had been so small at birth that her mother likely overlooked it. Katjinga's owner, Roland Adam, found the piglet alone and cold and brought it to his 8-year-old dog. (Photo by Fame Pictures)

A woman looks out of her house with a decorated doorway during Corpus Christi day in Zahara de la Sierra, southern Spain, May 29, 2016. The village of Zahara de la Sierra celebrated the feast of Corpus Christi (or Body of Christ in Latin) by covering the streets and facades of houses with the branches of trees and grass. (Photo by Jon Nazca/Reuters)

Francis Sierra, 23, smokes as she competes for the longest ash during the XVIII Habanos Festival in Havana, March 3, 2016. (Photo by Alexandre Meneghini/Reuters)

A Filipino flagellant crawls along a street on Maundy Thursday, in San Fernando city, Pampanga Province, north of Manila, Philippines, 24 March 2016. Many Filipino Catholic penitents mark the Holy Week by submitting to different forms of physical penance in the hopes of being forgiven for their sins. (Photo by Francis R. Malasig/EPA)

Russian marines attached to the anti- submarine ship Admiral Tributs show their skills during a demonstration at a park in Manila on January 5, 2017, as part of their five- day port- of- call activities in the country' s capital. (Photo by Ted Aljibe/AFP Photo)