Most pet cats will become timid or defensive when outdoors, but not Millie – after being adopted by her mountain-climbing owner Craig Armstrong, Millie has become a feline hiking and mountain-climbing legend.

Seth Casteel is an award-winning photographer and the New York Times Best Selling Author of Underwater Dogs. His new book, Underwater Puppies, was published September 16, 2014. Photo: “Underwater Puppies”: Popcicle. (Photo by Seth Casteel)

In this handout image provided by Perth 2011, HMB Endeavour, the replica of Captain James Cook's ship, is farewelled from Sydney Harbour accompanied by three Olympic class Laser yachts on April 16, 2011 in Sydney, Australia. The ship was farewelled from Sydney to start her circumnavigation of Australia, ending up in Freemantle where she will play a role in the Perth 2011 ISAF Sailing World Championships in December. (Photo by Richard Palfreyman/Perth 2011 via Getty Images)

Villager search for a place for the roasted pigs in Dalem Temple at Timbrah Village on February 27, 2014 in Karangasem, Bali, Indonesia. Usaba Dalem is an annual ritual held by the people of Timbrah Village, during this ritual all the villagers will cook roasted pigs and carry them to Dalem Temple as an offering to God and an expression of gratitude for a successful harvest. (Photo by Putu Sayoga/Getty Images)

Daniel Fox inside the Mendenhall Glacier, in September 2014, in Juneau, Alaska. Driving in an open-roofed jeep is no longer the fashionable way to see wildlife – as this adventurer shows. A keen wildlife photographer has circled islands in the south of Alaska, the United States, in a kayak to see spectacular scenery and animals. Daniel Fox, 40, from San Francisco spent three months travelling around the islands by kayak, meeting sea lions and brown bears along the way. (Photo by Daniel Fox/Barcroft Media)

The mystifying flow of motion. We can rarely appreciate its beauty. Though there are ways to capture it on film, allowing us to marvel at its complexity. Stephen Orlando is a photographer who takes pleasure highlighting the magnificence of aquatic sports by using the brilliance of light. The beauty of the images that he creates comes not only from the composition of the photo, but also from the way Stephen managed to show the color transitions between each stroke of the kayaker. Even the rapids do not stand in the way of the marvelous dance of light. (Photo by Stephen Orlando)

Refugees disembark and make their way to a camp at a hotel touted as the world's most northerly ski resort in Riksgransen, Sweden, December 15, 2015. (Photo by Ints Kalnins/Reuters)

“A snow roller is a rare meteorological phenomenon in which large snowballs are formed naturally as chunks of snow are blown along the ground by wind, picking up material along the way, in much the same way that the large snowballs used in snowmen are made”. – Wikipedia. Photo: Snow Roller. (Photo by The Daily Omnivore)