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)

The President tree is the name of a giant sequoia located in the Giant Forest of Sequoia National Park in the United States, east of Visalia, California. The tree is believed to be at least 3,200 years old.
The tree was named after President Warren G. Harding in 1923. Nearby trees include Chief Sequoyah, the 27th largest giant sequoia in the world, and the Congress Group, two dense stands of medium sized sequoias that represent the "House" and "Senate".

A woman walks past a painting by Jenny Saville entitled “Red Stare Head IV” on display in the Royal Academy of Arts' Summer Exhibition on June 2, 2011 in London, England. The Summer Exhibition is the world's largest open submission contemporary art show, now in its 243rd year, with over 12,000 entries received from 27 countries. The exhibition features over 1100 works of art including: painting, sculpture, photography, architecture and film, it officially opens to the public on June 7, 2011. (Photo by Oli Scarff/Getty Images)

An Edinburgh Fringe performer shows off his makeup on the Royal Mile, in the final weekend of this year's festival. The largest performing arts festival in the world has been running for the past three weeks and has enjoyed an increase in venues and visitors compared with previous years. (Photo by Jeff J. Mitchell/Getty Images)

Dogs and their owners dressed in Halloween costumes parade during the annual Haute Dog Howl'oween event in Long Beach, California on October 30, 2016. The parade, which claims to be the largest Halloween dog event in the world, sees hundreds of dogs and their owners dressed in colorful costumes celebrating the festival. (Photo by Mark Ralston/AFP Photo)

Women wearing Dirndl, a traditional Alpine folk dress, run to get a place in a tent for the opening of the 185th Oktoberfest beer festival in Munich, Germany, 22 September 2018. The Oktoberfest lasts until October 7 and is the world's largest beer festival. The beer festival typically draws over six million visitors. (Photo by Karl- Josef Hildenbrand/DPA/Alamy Live News)

The Tree Projects team spent 67 days documenting one eucalyptus regnans in the Styx valley of Tasmania. Using a combination of tree-climbing and elaborate arboreal rigging techniques, they produced an intimate portrait from an impossible perspective of one of the world’s largest individual flowering trees, which goes by several common names. These photos document the process that resulted in an extraordinary ultra high-definition photograph. Here: Haley nears the top of the tree. (Photo by Steven Pearce/The Tree Projects/The Guardian)

Chris Staring photographs a mysterious train graveyard in the heart of southern Bolivia, where the skeletons of British steam locomotives and rail cars rust away on the edge of the world’s largest salt flats. More than 100 rail cars and locomotives can be found in different states of decay in the train graveyard. (Photo by Chris Staring/Rex Features/Shutterstock)