A tourist poses for pictures with the mascot of the 2018 Boryeong Mud Festival at the Mud Square on Daecheon Beach 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 Friday. (Photo: Xinhua/Wang Jingqiang)

A tourist helps her friend smearing mud onto his face at the Mud Square on Daecheon Beach during the 2018 Boryeong Mud Festival in Boryeong. (Photo: Xinhua/Wang Jingqiang)

Tourists enjoy mud games at the Mud Square on Daecheon Beach during the 2018 Boryeong Mud Festival in Boryeong. (Photo: People's Daily/Chen Shangwen )

Tourists pose for pictures at the Mud Square on Daecheon Beach during the 2018 Boryeong Mud Festival in Boryeong. (Photo: People's Daily/Chen Shangwen )

Tourists enjoy mud games at the Mud Square on Daecheon Beach during the 2018 Boryeong Mud Festival in Boryeong. (Photo: People's Daily/Chen Shangwen )

Tourists enjoy mud games at the Mud Square on Daecheon Beach during the 2018 Boryeong Mud Festival in Boryeong. (Photo: People's Daily/Chen Shangwen )

A tourist enjoys mud slide at the Mud Square on Daecheon Beach during the 2018 Boryeong Mud Festival in Boryeong. (Photo: Xinhua/Wang Jingqiang)

Tourists enjoy mud games at the Mud Square on Daecheon Beach during the 2018 Boryeong Mud Festival in Boryeong. (Photo: People's Daily/Chen Shangwen )

Visitors enjoy amusement facilities during the 2018 Boryeong Mud Festival in Boryeong. (Photo: People's Daily/Chen Shangwen )