A tourist is buried in sand during the Boryeong Mud Festival at Daecheon beach in Boryeong, South Korea, July 16, 2016. (Photo by Kim Hong-Ji/Reuters)





Tourists play with mud during the Boryeong Mud Festival at Daecheon beach in Boryeong, South Korea, July 16, 2016. (Photo by Kim Hong-Ji/Reuters)





Tourists play in a mud pool during the Boryeong Mud Festival at Daecheon beach in Boryeong, South Korea, July 16, 2016. (Photo by Kim Hong-Ji/Reuters)





Tourists play in a mud pool during the Boryeong Mud Festival at Daecheon beach in Boryeong, South Korea, July 16, 2016. (Photo by Kim Hong-Ji/Reuters)





A tourist plays with mud during the Boryeong Mud Festival at Daecheon beach in Boryeong, South Korea, July 16, 2016. (Photo by Kim Hong-Ji/Reuters)





Tourists play in a mud pool during the Boryeong Mud Festival at Daecheon beach in Boryeong, South Korea, July 16, 2016. (Photo by Kim Hong-Ji/Reuters)





A tourist covered with coloured mud on his face poses for photographs during the Boryeong Mud Festival at Daecheon beach in Boryeong, South Korea, July 16, 2016. (Photo by Kim Hong-Ji/Reuters)





Tourists play with mud during the Boryeong Mud Festival at Daecheon beach in Boryeong, South Korea, July 16, 2016. (Photo by Kim Hong-Ji/Reuters)





A festival-goer poses for a photo after a bath in a mud pool during the 18th Boryeong Mud Festival on Daecheon beach in Boryeong City, some 190 kilometers west of Seoul, South Korea, 16 July 2016. During the festival tourists flock to the area to experience the beneficial properties of the Boryeong mud, as well as for a variety of entertainment events. (Photo by Jeon Heon-Kyun/EPA)





Tourists rest as they cover themselves with mineral-rich mud on a bank of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)





Tourists rest as they cover themselves with mineral-rich mud on a bank of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)





A general view shows a tourist camp on the banks of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)





Tourists rest as they cover themselves with mineral-rich mud on a bank of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)





Tourists rest as they cover themselves with mineral-rich mud on a bank of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)





A tourist reads a magazine as he floats in the salt waters of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)





A man covered with mineral-rich mud smiles on a bank of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)