Children are engulfed by foam during the Bubble Show event in Beijing, China, Sunday, June 26, 2016. Thousands of residents enjoy colored foam churned out by machines along a running track at the event designed for children and parents' interaction. (Photo by Ng Han Guan/AP Photo)

Visitors look at tropical fish transported from Japan's southern island of Okinawa displayed in a giant 14-ton fish tank at the Sony Square event space in Tokyo on July 17, 2016. The 45-day-long summer exhibition will be held through August 28 to display sea creatures common to the waters around Okinawa. (Photo by Kazuhiro Nogi/AFP Photo)

Tsetse, six-year-old daughter of Dukha herder Erdenebat Chuluu, sits among her family's reindeer in a forest near the village of Tsagaannuur, Khovsgol aimag, Mongolia, April 21, 2018. Nyamaa is an ethnic Darkhad, herders of northern Mongolia who have historically inhabited the steppe that borders the Taiga forests. (Photo by Thomas Peter/Reuters)

“Joker” movie production tries to hide Joaquin Phoenix's clown make-up and green hair with umbrella and a long black cloth over his head as he was walking with the help of assistant and bodyguard to the set of “Joker” filming at a Bronx train station on September 22, 2018. (Photo by The Mega Agency)

Eagle Prime (MK3), a giant robot by MegaBots Inc. which manufactures giant piloted humanoid fighting robots headquartered in Berkeley, California on October 18, 2017. (Photo by Courtesy Michael Mauldin/Reuters/MegaBots Inc)

Girls dressed in traditional costumes run as men throw water on them as part of Easter celebrations during a presentation to the media in Mezokovesd, Hungary, April 13, 2017. (Photo by Laszlo Balogh/Reuters)

Fans are seen at the 143rd Kentucky Derby on May 6, 2017 in Louisville, Kentucky. (Photo by Michael Hickey/Getty Images)

Soma-Nomaoi is a festival that recreates a battle scene from more than 1,000 years ago. It is annually held for 4 days from July 22 to 25 in Haramachi City, Fukushima Prefecture, in the eastern part of Japan. In this historical event, 600 mounted samurai in traditional Japanese armor, with long swords at their side and ancestral flagstaffs streaming from their backs, ride across open fields. Soma-Nomaoi has been designated an Important Intangible Folk Cultural Property.

Photo: A young woman (C) clad in samurai costume leads other local poeple as she rides her horse during a parade at the annual Soma Nomaoi festival in Minamisoma, Fukushima Prefecture, on July 28, 2012. The traditional full-scale festival kicked off for the first time after the accident of the Fukushima Dai-ichi Nuclear Power Plant following the massive earthquake and the tsunami on March 11, 2011. (Photo by Toru Yamanaka/AFP Photo)