A lake doubles everything. The fireworks rise above Suwa, and then they fall again, perfect and inverted, into the still water below—so that you are never quite sure where the sky ends and the reflection begins. Forty thousand shells, one of the largest counts in all of Japan, and a basin of mountains to hold the sound. The festival began in 1949, in the hard years after the war, as a wish for recovery. The geography does something remarkable to it. Ringed by peaks, the valley catches the concussion of each shell and throws it back, so that the explosions arrive twice—once from the sky, once from the hills—and the light arrives twice too, once above and once across the mirror of the lake. This is mid-August, the season of Obon, when the spirits of the dead are said to return home. Half a million people gather at the water's edge, on hotel balconies, on the grass along the shore. A Niagara of fire pours across the surface; a rainbow star-mine hangs in the dark. There is a softness to watching fireworks over water that you do not get anywhere else, a doubling that feels less like spectacle than like memory—the thing itself, and its echo, rising and falling together over the oldest lake in the mountains.