Ten thousand dancers, each carrying a broad hat decorated with red safflower blossoms. The Hanagasa Festival moves through central Yamagata over three evenings in August, and the sound — Yassho, Makasho, repeated by thousands of voices in rhythm with the dance — becomes, by the second evening, the sound of the city itself. The hanagasa hat takes its flower from benibana, the safflower cultivated in the Yamagata basin for centuries and used to produce the red dye that once made this region wealthy. The festival was created in the twentieth century, which gives it a deliberately joyful character. During certain portions of the parade, anyone can join the line of dancers. The steps are simple enough to learn by watching. On the last night, when the procession has been going for hours and the crowd has loosened, and the dancers are still calling out with the same energy as the first hour — that is when you understand why a city would choose to do this every August. The answer is not complicated. It is the dancing.