These stunning images look to highlight the amazing natural beauty that can be found across the United States. The U.S. Department of the Interior (DOI) recently released their Best of 2015 list, featuring a variety of animals, weather conditions and landmarks. Included in the list are gleaming auroras, adorable groups of otters and owls, and breath-taking shots across the likes of the Grand Canyon and national parks. Each of the spectacular shots, all of which were taken during 2015, featured on the Department of the Interiors Instagram account throughout the year, taken by both members of staff and members of the public. Here: Arches, National Park. (Photo by Caters News)

These black-and-white photos are taken from the new book “Armoured Warfare in the First World War 1916 – 1918” by Anthony Tucker-Jones and published by Pen & Sword Military. Here: British troops hitch a ride on a Mark IV after the massed tank fleet spearheading attack at Cambrai on November 20, 1917. (Photo by Anthony Tucker-Jones/Mediadrumworld.com)

The National Geographic Photo Ark is a travelling exhibition of photographer Joel Sartore’s quest to create a photo archive of biodiversity around the world. So far, Sartore has captured studio portraits of more than 6,000 species – a number that he hopes to double. On 1 July, the ark will open at Melbourne zoo – the first time it has been exhibited in the southern hemisphere. More than 50 portraits will be on display, including many of Australian endangered animals being protected by programs at the zoo itself. These captions have been edited from text supplied by Melbourne zoo. Here: Barking owl. (Photo by Joel Sartore/National Geographic Photo Ark/The Guardian)

What do you imagine when you look through a key hole? Do you imagine seeing a Wonderland with a sinister Queen of Heart ruling over a magical kingdom? Or you might imagine an eye staring back at you, if you’re a fan of horror movies. Least of all do you expect seeing a picturesque view of St. Peter’s Dome, perfectly framed by green hedges. Is it a lucky coincidence, or was it intended by the maker? We might never know. However, this became a curious sightseeing spot for many tourists who visit Rome. Thus, if you’re ever in the area of Priorato dei Cavalieri di Malta, be sure to peep into this key hole.

Manu Brabo was born in Spain in 1981. After studying Photography in The School of Arts and Crafts in Oviedo, he moved to Madrid where he started Journalism in Carlos III University while he was working as a photographer for several humble newspapers and agencies. In 2011, Manu was held captive and then released by by Libyan forces. Brabo, along with fellow AP photographers were awarded the 2013 Pulitzer Prize for Breaking News Photography. Here: a Syrian man cries while holding the body of his son, killed by the Syrian Army, near Dar El Shifa hospital in Aleppo, Syria, Wednesday, October 3, 2012. (Photo by Manu Brabo/AP Photo)

Photographer Gregg Segal travelled the world to document children and the food they eat in a week. Partly inspired by the increasing problems of childhood obesity, he tracked traditional regional diets as yet unaffected by globalisation, and ironically, found that the healthiest diets were often eaten by the least well off. (Photo by Gregg Segal/The Guardian)

In time for Halloween the Maniac Pumpkin Carvers, creative art studio, held the Cotton Candy Machine workshop in Brooklyn, N.Y., demonstrating techniques and tools to create intricate pumpkin art. Maniac Pumpkin Carvers, which focuses on elevating the art of pumpkin carving, were a past winner of the Food Network's Halloween Wars. Their work has been displayed at MOMA, the Whitney Museum and Yankee Stadium. Here: A Tara Bonethrower pumpkin created by the Maniac Pumpkin Carvers at Cotton Candy Machine in Brooklyn, N.Y. on October 18, 2014. (Photo by Siemond Chan/Yahoo Finance)

These otherworldly images give a rare glimpse inside caves barely ever seen by the human eye. With its peculiar pools of water and strange colored sediments, the bizarre looking tunnels of the Shakuranskaya cave could be a set straight out of a science fiction film. Found in the disputed region of Abkhazia, around 75 miles outside of Sochi, Russia, it is rumored the incredible underground chambers were formed after a huge earthquake struck the area in 1892. After causing part of a nearby mountain to collapse into the Amtkel River, it is thought the dam-like affect has created a series of interconnecting underground tunnels. Here: a large pool of water inside one of the tunnels. (Photo by Vladimir Mulde/Caters News)