Photographer Andy Hall joins the thousands of fans from west Africa who have gathered for Baaba Maal's annual Blues du Fleuve festival in Senegal. Here: Dancers wait to perform on stage. (Photo by Andy Hall/The Observer)

A racegoer cheers on their horse at Cheltenham Racecourse for ladies day on March 16, 2011 in Cheltenham, England.

Director Lars Von Trier attends the “Melancholia” photocall at the Palais des Festivals during the 64th Cannes Film Festival on May 18, 2011 in Cannes, France. (Photo by Pascal Le Segretain/Getty Images)

Hot air balloons fly over Igualada during an early flight as part of the European Balloon Festival on July 10, 2014 in Igualada, Spain. The early morning flight of over 30 balloons was shorter than expected due to windy weather. This flight is organised as a curtain raiser for the four-day European Balloon Festival. Now is the 18th year of the most important hot air Balloon event in Spain and one of the biggest in Europe. (Photo by David Ramos/Getty Images)

Singers Steven Tyler (L) and Nicole Scherzinger perform onstage at the iHeartRadio Music Festival held at the MGM Grand Garden Arena on September 24, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images for Clear Channel)

Bulls fight during the annual Bullfighting Festival on March 17, 2010 in Cheongdo, South Korea. More than 130 bulls from South Korea and abroad charge and lock horns in the annual festival which was run March 21, 2010. The bulls are grouped into three weight categories and fight head on until one of the bulls turns its head and runs away. (Photo by Chung Sung-Jun/Getty Images)

“A Hadaka Matsuri (“Naked Festival”) is a type of Japanese festival, or matsuri, in which participants wear a minimum amount of clothing; usually just a Japanese loincloth (called fundoshi), sometimes with a short happi coat, and rarely completely naked. Whatever the clothing, it is considered to be above vulgar, or everyday, undergarments, and on the level of holy Japanese shrine attire. Naked festivals are held in dozens of places throughout Japan every year, usually in the summer or winter. The most famous festival is held in Okayama, where the festival originated. Every year, over 9,000 men participate in this festival”. – Wikipedia

Photo: Japanese men wear loincloths as they splash about in freezing cold water during Saidaiji Naked Festival, at Saidaiji Temple on February 18, 2012 in Okayama, Japan. (Photo by Buddhika Weerasinghe/Getty Images)

A Dongria tribe girl holds her traditional weapon and dance on the last day of their two days long Niyamraja Festival atop of the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)