Fireworks festivals are more of a tradition in Japanese culture than you'd expect. In contrast, Americans would never look at fireworks as part of the culture. More important is the day you shoot them off rather than the fireworks festival itself. In Japan, once summer starts, there is a fireworks festival *literally* almost every other day until the end of August. And by comparison with the ones I've seen in the US, they destroy 99% of them. Even Disney's (which I think says a lot); especially when you consider that a small town/suburb of tokyo can outbeat a huge multi-billion corporation like Disney when it comes to putting on a fireworks show. Point and case: Japan's fireworks are amazing.
Usually they start around 7ish and last until 8:30 if not later. However, don't be fooled by the start and end times. The trains are brutally crowded and when you get to the station stop, there's usually still a good 30min walk to the fireworks location through crowds of people. Even then, if you get there "on time" you still will have trouble finding a place to sit down. These festivals are more popular in Japan than you can imagine. The crowd of people is sometimes overwhelming but once you find a place to squeeze in, its well worth the wait the walk and the effort. That being said, I recommend sticking to groups of 2 or 3 maybe 4 tops if you decide to go. A large group is almost impossible to sit unless you leave at like 4:00 for the festival in an attempt to get there around 5:30. Otherwise don't even imagine going in a group of 5 and finding a place for you all to sit with each other.
Another plus of these festivals is that when you get there the streets are lined with food vendors, beer/sake/wine sellers, etc etc. Its a great chance to try a variety of Japanese foods if you haven't had the chance. Yakiniku, takoyaki, man, as well as real Japanese sake are all on sale on the road to the fireworks area. If you're pressed for time, you can catch your dinner on the way : )
I've only been to two festivals, but one of the most amusing things is the limitation of Japanese vocabulary to describe the fireworks. In English we have such an immense selection of words we can use, to the extent opening the dictionary or a thesaurus would offer at least one word you've never seen before. So if we are watching fireworks we could say dazzling! pretty! beautiful! wow! amazing! awesome! cool! magnificent! etc.
The Japanese tend to stick to "Sugoi" (sometimes pronunced suge by men) and "kirei." Feel free to get creative but expect weird looks because you'll end up sounding like a gaijin lol.
So if you go to a hanabi taikai (fireworks festival) expect to here repetitively those two words without any exceptions. Either way enjoy it!
