Enburi(えんぶり) is the folk performing art that dancers wearing hats in the shape of the horse head dance with a shake of the head to pray for a good harvest.
Enburi is held in five prefectures including Fukushima, Tamagata, Miyagi, Iwate and Aomori.
spots to see flashing fireflies (Japanese version only):
https://www.enjoytokyo.jp/feature/season/hotaru/ (Tokyo and surrounding areas)
fireworks displays (Japanese version only):