The origin of Aoi Matsuri, one of Kyoto's 3 great festivals, goes back more than 1,500 years. Diviners advised the people to ride horses in prayer for bumper crops and to appease the Kamo deities, who were causing storms and floods. Emperors thereafter paid homage to Shimogamo Jinja Shrine and Kamigamo Jinja, and solemnly performed these now-ancient rituals that are reminiscent of the dynastic culture. Aoi Matsuri, its splendid parade and rare customs are full of mystery, even for Japanese.