A woman hangs strips of salted meat she collected from different places during the Muslim's Eid al-Adha or Festival of Sacrifice, in Lahore, Pakistan, Sunday, August 2, 2020. Pakistanis are celebrating the Eid al-Adha, or the Feast of the Sacrifice, to mark the willingness of the Prophet Ibrahim – Abraham to Christians and Jews – to sacrifice his son. During the holiday Muslims slaughter sheep and cattle, distribute part of the meat to the poor. (Photo by K.M. Chaudary/AP Photo)

A blue crab, a highly invasive alien species, is seen at Lio Piccolo during the reforestation day on April 05, 2025 in Venice, Italy. The island of Lio Piccolo in the northern lagoon of Venice is being replanted with 16,000 new trees that will protect the salt marsh ecosystem that is fundamental to the natural health of Venice and the lagoon by WOWnature project, an Etifor initiative. (Photo by Simone Padovani/Getty Images)

A monolith placed in the Utah wilderness in November 2020. New clues have surfaced in the disappearance of the gleaming monolith that seemed to melt away as mysteriously as it appeared in the red-rock desert. A Colorado photographer told a TV station in Salt Lake City that he saw four men push over the hollow, stainless steel structure last Friday night. (Photo by Terrance Siemon/AP Photo)

A camel rests at a fuel station in the Judean desert near the West Bank city of Jericho January 11, 2015. Reuters photographers from Mali to Mexico have shot a series of pictures of fuel stations. Whether it is plastic bottles by the roadside in Malaysia or a futuristic forecourt in Los Angeles, fuel stations help define our world. Oil prices steadied above $48 a barrel on Tuesday, recovering from earlier losses as the dollar weakened against the euro. Oil prices have dropped nearly 60 percent since peaking in June 2014 on ample global supplies from the U.S. shale oil boom and a decision by OPEC to keep its production quotas unchanged. (Photo by Baz Ratner/Reuters)

The legs of camel and sheep for the “Living Nativity” scene, and Rockettes, of the “Radio City Christmas Special”, are juxtaposed as they pose for photos outside New York's Radio City Music Hall, Tuesday, October 28, 2014. The show is scheduled to open Friday, November 7, 2014 and continue through Wednesday, December 31, 2014. The “Living Nativity” has been part of the Christmas Spectacular since its inception in 1933. (Photo by Richard Drew/AP Photo)

A Syrian boy plays with the head of a sacrificed sheep at a DIP camp for Interally Displaced Persons near the town of Aqrabat in Syria's northern Idlib province on August 12, 2019. Known as the “big” festival, Eid Al-Adha is celebrated each year by Muslims sacrificing various animals according to religious traditions, including cows, camels, goats and sheep. The festival marks the end of the Hajj pilgrimage to Mecca and commemorates Prophet Abraham's readiness to sacrifice his son to show obedience to God. (Photo by Aaref Watad/AFP Photo)

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.

A vendor decorates a sacrificial camel ahead of the Eid al-Adha festival, in Karachi, Pakistan, 23 August 2016. Eid al-Adha is the holiest of the two Muslims holidays celebrated each year, with this year will be celebrated on 02nd September. Eid al-Adha marks the yearly Muslim pilgrimage (Hajj) to visit Mecca, the holiest place in Islam. Muslims slaughter a sacrificial animal and split the meat into three parts, one for the family, one for friends and relatives, and one for the poor and needy. (Photo by Rehan Khan/EPA)