This is the summer of the flower hats. The Hanagasa Festival fills the streets of Yamagata with dancers holding straw hats adorned with safflowers—the hanagasa that gives the festival its name—as they move to the rhythmic chant of "Yassho, makasho." It is one of the defining celebrations of the Tohoku summer, and around it the fireworks rise. The shells open over the banks of the Mamigasaki River, at the foot of the sacred Mount Zao, the dancers' chant still echoing in the warm air. Yamagata is the safflower city—in the Edo period, the cultivation of this red-orange flower, used to make precious dye and cosmetics, brought the region its wealth, carried south to Kyoto along the old trade routes. Flowers run all through it. The flowered hats in the dancers' hands, the safflower history beneath the city's prosperity, and now the fireworks—hanabi, written with the characters for "flower" and "fire," the flowers of fire blooming above the river. In Yamagata the summer is colored by flowers of every kind, woven from petals and dye and light, the whole season flowering at once in the northern dark.