Stones collected and categorised by shape (fish) are seen at the home workshop of Luigi Lineri in Zevio, near Verona, Italy, June 10, 2016. Luigi Lineri's home workshop is covered in stones – tens of thousands of them. They resemble animal heads, human faces and other forms, and the artist and poet believes may have been shaped by prehistoric humans. (Photo by Alessandro Bianchi/Reuters)

In this May 24, 2016 photo, a young boy descends the Qullqip'unqu mountain looking out at the tens of thousands of pilgrims gathered to celebrate the three-day festival Qoyllur Rit’i, translated from the Quechua language as Snow Star, in the Andean Sinakara Valley, in Peru's Cusco region. The celebration that mixes Catholic and indigenous beliefs honors Jesus as well as the area’s glacier, which is considered sacred among some indigenous people. While the native celebration is far older, the Christian part of the ritual stretches back to the 1700s, when Jesus is said to have appeared to a young shepherd in the form of another boy. (Photo by Rodrigo Abd/AP Photo)

Nino, a ten-year-old toreador apprentice of the French Tauromachy Centre, nicknamed El Nino, touches a practice bull at the bullring of Garons, near Nimes, September 25, 2013. Since 1983, the French Tauromachy Centre in Nimes has trained some 1,000 youths in the art of bullfighting. Twenty of them have gone on to become professional matadors, facing fighting bulls in the arena. Twice a week, students take courses with a matador to learn the movements and gestures of the bullfighter in the ring, but without an animal present. Students train with calves in the surrounding fields during spring, and regularly participate in beginner's bullfights (becerradas) without killing calves. Solal has been taking courses for three years and Nino, for just a year now. Both are normally enrolled in French public schools, but have one thought in mind – bullfighting. They share a passion linked to the city of Nimes, famous for its ferias and bullring. (Photo by Jean-Paul Pelissier/Reuters)

Pregnant Tibetan antelopes move across the Qinghai-Tibet highway in Hoh Xil, northwest China's Qinghai Province, May 29, 2023. A growing number of pregnant Tibetan antelopes are migrating to the heart of northwest China's Hoh Xil National Nature Reserve to give birth, according to the reserve's management office. Every year, tens of thousands of pregnant Tibetan antelopes start their migration to Hoh Xil in around May to give birth and leave with their offspring in late July. (Photo by Xinhua News Agency/Rex Features/Shutterstock)

Boys pan for gold on a riverside at Iga Barriere, 25 km (15 miles) from Bunia, in the resource-rich Ituri region of eastern Congo February 16, 2009. Ituri is one of many areas of the country to have experienced bitter ethnic conflict between rival tribes in recent years. Massacres have left tens of thousands dead. It is this fighting that led U.S. authorities to take the unprecedented step of naming Congo in section 1502 of the Dodd-Frank financial regulation act, which says U.S.-listed companies that source gold, tungsten, tantalum and tin from Congo or its neighbours must assure the U.S. stock exchange regulator that their business is not helping fund conflict. (Photo by Finbarr O'Reilly/Reuters)

An Indian artist gives the finishing touches to a figure of the elephant-headed Hindu god Ganesha at a workshop ahead of the Ganesh Chaturthi festival in New Delhi on September 15, 2015. The idol is meant for the forthcoming festival Ganesha Chaturthi, a ten-day long event which is celebrated all over India. During the Ganpati festival, that is celebrated as the birthday of Lord Ganesha, idols of the Hindu deity are worshipped at hundreds of pandals or makeshift tents before they are immersed into water bodies. This year, the festival starts on 17 September 2015. (Photo by Sajjad Hussain/AFP Photo)

Jacob's Well is a perennial karstic spring in the Texas Hill Country flowing from the bed of Cypress Creek, located northwest of Wimberley, Texas. The twelve foot (four meter) diameter mouth of the spring serves as a popular swimming spot for the local land owners whose properties adjoin Cypress Creek. From the opening in the creek bed, Jacob's Well cave descends vertically for about thirty feet (ten meters), then continues downward at an angle through a series of silted chambers separated by narrow restrictions, finally reaching a depth of one hundred and twenty feet (forty meters). Until the modern era, the Trinity Aquifer-fed natural artesian spring gushed water from the mouth of the cave, with a measured flow in 1924 of one hundred and seventy gallons per second (six hundred and forty liters per second) discharging six feet (two meters) into the air. The spring is the greatest source of water recharging the Edwards Aquifer.