National Geographic has created “Air, Land & Sea: the 50 greatest wildlife photographs” exhibition. Here: CT4 Crocodile cave on the Salamat river. Set up with Nathan Williamson last chip rain came while we were with the nomads. (Photo by Michael Nichols/National Geographic)

One of the last incoming trains arrives outside the main train station after Deutsche Bahn cancelled all train traffic in Germany due to heavy storms, Frankfurt, Germany, Thursday, January 18, 2018. (Photo by Michael Probst/AP Photo)

Tali Spira of Baltimore, Maryland lets the wind aid in her Flow Art style dance moves (using silk material and fans) at the Tidal Basin in Washington, D.C. on March 25, 2022. She danced amid the backdrop of the cherry blossom trees that were still at their peak. (Photo by Michael S. Williamson/The Washington Post)

Weddell seal numbers in 2025 have declined sharply on Signy Island, part of the South Orkney Islands in the Southern Ocean, where British Antarctic Survey researchers have tracked seal populations for nearly 50 years to understand the impact of melting sea ice. (Photo by Michael Dunn/The Times)

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)

Looking for a reason to visit the Philippines? This mermaid school should do the trick. No, seriously, there’s an actual school that will teach you how to be a mermaid. It’s called the Philippines Mermaid Swimming Academy. (Photo by Philippine Mermaid Swimming Academy/Exclusivepix Media)

An athlete dressed as a clown jumps into the Mediterranean sea as he takes part in the Copa Nadal in the Spanish port of Barcelona in Barcelona, Spain, Sunday, December 25, 2016. The Copa Nadal (Christmas Cup) is a traditional swimming competition that takes place in Barcelona every December 25th, where participants swim 200 meters in the open sea in the port of Barcelona. (Photo by Manu Fernandez/AP Photo)

Participants of the 77th edition of the annual Christmas swimming 'Coupe de Noel' jump into the waters of Lake Geneva, in Geneva, Switzerland, 20 December 2015. More than 1,540 men and women braved the water temperature of just 8 degrees Celsius as they swam a 120 meters distance at the traditional Christmas swimming in Geneva. (Photo by Salvatore Di Nolfi/EPA)