Željava Air Base, situated on the border between Croatia and Bosnia and Herzegovina under Plješevica Mountain, near the city of Bihać, Bosnia, was the largest underground airport and military air base in the former Yugoslavia, and one of the largest in Europe. (Photo by Thomas Windisch/Exclusivepix Media)

These stunning coloured images show detailed x-ray images of everything from skulls to light bulbs. Artist Paula Fontaine, from Westminster Massachusetts, created the images using a process called digital map painting. To create the images the x-ray emission source – the head of the machine on an arm which focuses the beam – is placed over the object. Paula then retreats behind a shielded screen before activating the x-ray exposure. Here: Brain storm, conceptual composite X-ray. (Photo by Paula Fontaine/Barcroft Media)

An Andalusian horsewoman waits for the animal to drink water before a classical dressage contest during the Sacab Andalusian Horse Show in Coin, southern Spain, April 12, 2015. (Photo by Jon Nazca/Reuters)

Hindu devotees perform rituals during the Bol Bom pilgrimage, on the outskirts of Kathmandu, Nepal, Monday, August 8, 2016. During this pilgrimage, devotees walk miles barefooted before offering water collected from Bagmati river, at the Pashupatinath temple in Katmandu. Shravan Somwar or Monday of Hindu calendar month of Shravan is considered auspicious for offering prayers to Lord Shiva, the god of destruction. (Photo by Niranjan Shrestha/AP Photo)

Thousands of species of amphibians are endangered and hundreds have already disappeared, but in recent years, a team of scientists and conservationists have re-discovered some of these “lost” species and uncovered previously unknown varieties. Here: Miniature glass frog. (Photo by Robin Moore)

An employee feeds a one-week-old coati cub with a bottle of milk at the Royev Ruchey zoo in the suburbs of Krasnoyarsk, Siberia, October 10, 2014. The mother of three cubs refused to nurse them, according to zoo employees. (Photo by Ilya Naymushin/Reuters)

Revellers attend drag extravaganza “Bushwig” that was cancelled last year due to the coronavirus disease (COVID-19) pandemic in New York City, New York, U.S., September 12, 2021. (Photo by Stephanie Keith/Reuters)

“Ary Borges and his family live in southern Brazil like most families the Borges' love animals and have an array of cats living in their home. The only difference between the cats owned by the Borges family and the cat that is cuddled up on your lap as you read this is the Borges' cats weigh over 700 pounds and could kill you just as soon as look at you. The Borges family shares their home with nine tigers, two lionesses, a chimp and a Chihuahua”. – Amanda Schiavo via Latin Times. Photo: The Borges' family pet dog, Little, is placed on the back of Tom, their tiger, for a photo to be taken, in Maringa, Brazil, Friday, September 27, 2013. (Photo by Renata Brito/AP Photo)