Firework Festival
You'll be able to enjoy the big firework displays, Hanabi Taikai, all over Japan in August. It is one of the most spectacular summer events in Japan.
Iwami Festival
There are a lot of local festivals in Japan and most of them are held annually and celebrate events like the coming of the farming season, the harvest, or the commemoration of historical events. Usually, the bigger festivals are held over several days in spring.