Tourists pose for pictures at the Mud Square on Daecheon Beach during the 2018 Boryeong Mud Festival in Boryeong, Chungcheongnam-do of South Korea, July 14, 2018. The 10-day 2018 Boryeong Mud Festival, one of the most famous summer events in South Korea, kicked off here Friday. (Xinhua/Wang Jingqiang)