Men take part in the annual mud festival in Yotsukaido City, Japan. The festival -- called the "hadaka matsuri," or "naked" festival -- involves a wide range of rituals in muddy rice paddies meant to bring a good harvest and good fortune. The centuries-old rites are thought to have been a way for farmers to prepare themselves for the planting season after having spent most of the winter inside. The most famous rituals involve mud- throwing and mud-wrestling battles during which teams of men carrying other men on their shoulders try and knock over the competition.