A cenote is a natural phenomenon, a sinkhole in the Earth’s surface. The Yucatan Peninsula in Mexico has an estimated 7,000 cenotes because it is primarily made up of porous limestone. For millions of years, rainfall slowly ate away at the limestone and a huge system of underground caves and caverns was formed. Many filled with water from rain or from the underground water table. When the roof of a water filled cave collapses, a cenote is born. The water found in a cenote may be fresh water, salt water, or both. Structurally it may be completely open, like a lake, almost completely closed with just a small opening at the top, or somewhere in between.

During work hours on one of the busiest streets of Baku, Azerbaijan’s capital, parking attendant Rafael Veyisov wipes off the dust on cars with his fingers, slowly contouring the shapes of tall buildings and flying birds. In his artwork, he generally illustrates real towns to educate people about other countries, but sometimes he also lets his imagination run wild and produces impressive original works. Surprised by his talent, the car owners who regularly leave their vehicles in Rafael’s care, often leave them dirty just to give him an excuse to play around, and take photos of his beautiful artworks.

With their wings at full length, these beautiful golden eagles soar through the skies in a glorious training session to hunt their prey. Others sit on the arms of their owners and trainers. Batzaya Choijiljav, 41, from Mongolia has taken these magnificent pictures at the annual traditional Kazakhs festival, October 2015. (Photo by Batzaya Choijiljav/Caters News)

A photograph of a dog taken from underneath on December 2016 in VA, Canada. Forget the cats, itÌs just raining dogs! A creative duo have come up with an innovative way to raise money for animal welfare; photographing dogs as youÌve never seen them before. Professional photographer Jason Kenzie and designer Tania Ryan have created a unique set of images from the underside of dogs, named The Underdogs Project. The project will be featured as a 2017 calendar, with each month belonging to a quirky canine. (Photo by The Underdogs Project/Barcroft Images)

Flying pigeons pass over Nepalese street vendors near the earthquake damaged UNESCO World Heritage Site, Durbar Square in Kathmandu on May 20, 2015. Nearly 8,500 people have now been confirmed dead in the disaster, which destroyed more than half a million homes and left huge numbers of people without shelter with just weeks to go until the monsoon rains. (Photo by Ishara S. Kodikara/AFP Photo)

Ricardo Azevedo rides his Honda NX 200 motorbike, which he converted to be powered by water, in Salto, northwest of Sao Paulo, Brazil, August 6, 2015. The Sao Paulo civil servant built the motorbike, which can cover up to 500 kilometres (311 miles) fuelled by just one litre of water. Dubbed “Moto Power H2O” the bike is powered by the process of electrolysis, which breaks the water molecule down into its constituent elements. (Photo by Nacho Doce/Reuters)

A store staff walks past other staffs dressed up as Stormtrooper and Death Star Gunner (R) from the film “Star Wars” before launching the film's new toys at Loft Variety Store in Shibuya shopping district in Tokyo, September 3, 2015. New “Star Wars” toys and other merchandise were released in stores across Japan just after midnight local time during a global rollout of the popular products. (Photo by Toru Hanai/Reuters)

A municipal worker who helped with traffic control near a school is presented with flowers at the end of the national college entrance examinations, known as the gaokao, in Beijing, Friday, June 10, 2022. More than 11 million high school students throughout China took the annual college entrance exams which started on Tuesday after the country has just overcome severe COVID-19 outbreaks in Shanghai and Beijing, according to state media. (Photo by Ng Han Guan/AP Photo)