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.

The Atlantic Ocean Road or the Atlantic Road (Norwegian: Atlanterhavsveien) is a 8.3-kilometer (5.2 mi) long section of County Road 64 that runs through an archipelago in Eide and Averøy in Møre og Romsdal, Norway. It passes by Hustadvika, an unsheltered part of the Norwegian Sea, connecting the island of Averøy with the mainland and Romsdalshalvoya peninsula. It runs between the villages of Karvag on Averoy and Vevang in Eida. It is built on several small islands and skerries, which are connected by several causeways, viaducts and eight bridges – the most prominent being Storseisundet Bridge.

Located at La Casa Del Arbol or “The Treehouse” in Baños, Ecuador, this small house was built for the stunning view on the Tungurahua Volcano it offers. But the real attraction is the swing attached to one of the tree's branches. It is far from your average swing, and it is surnamed the "Swing at the End of the World" for a good reason. Located off a giant cliff at over 2,600 meters above sea level and with absolutely no safety features, this swing promises a serious thrill to whoever is brave enough to ride it.

Bouboule, an English bulldog rests in its hotel room at Actuel Dogs on April 19, 2011 in Vincennes, France. Opened in November 2010 by Devi and Stan Burun, Actuel Dogs is a five-star luxury hotel for dogs with four single rooms and two suites. With the aim of meeting the dogs' needs, the hotel offers activities including doggy walks, doggy rando (hiking), doggy jogs, doggy velo (running next to a bike) and other services such as dog massage. The hotel also caters to the needs of people living in small appartments or who don't have the time to walk their dogs. (Photo by Franck Prevel/Getty Images)

Jane Howorth from national charity the British Hen Welfare Trust holds Liberty the last ex-battery hen to be rehomed on December 29, 2011 in Chulmleigh, England. The rehoming of Liberty signifies the end of the small battery hen cage, which has been phased out and replaced by enriched cages in preparation of the European Union directive banning the smaller cages from January 1, 2012. (Photo by Matt Cardy/Getty Images)

Taiwanese artist Hank Cheng poses with his miniature model of Taipei street scenes, in New Taipei City, Taiwan on June 17, 2018. While some of the vehicles used in Cheng's street scenes are bought in shops, all the buildings and small details like the magazines and the furniture for his model houses are created from scratch. (Photo by Tyrone Siu/Reuters)

To an outsider, their passion is at times illegal and often on the verge of life and death. But climbing rooftops of high-rise buildings and exploring abandoned facilities is in the blood of these young Muscovites. The small group calls itself “Rudex”, which stands for “roof and decay exploration”, and is akin a Western youth craze known as urbex or “urban exploration” of man-made structures. Here: Urban explorer Vad Him of Rudex team jumps whilst on a rooftop in Moscow, Russia, August 14, 2017. (Photo by Maxim Shemetov/Reuters)

Masked penitents holds their crosses during spring “Romeria Cruceros de Arce”, in Roncesvalles, northern Spain, Sunday, May 10, 2015. Every year on the second Sunday in spring, people with crosses march from their small Pyrenees towns to Roncesvalles Church in tribute of the Virgin. (Photo by Alvaro Barrientos/AP Photo)