Bentenjima is a large island in Lake Hama, just a few stops from Hamamatsu. One of the largest free fireworks festivals in the area is usually held here the first weekend in July (this festival is heavily promoted, so keep your eyes peeled). When you pass Bentenjima station you will be directed where you need to go as the area is very small.
Bentenjima Station is on the JR Tokaido Line and is west of the city of Hamamatsu. If you are coming from Tokyo, go to Hamamatsu (Hikari or Kodama Shinkansen) and transfer to the Tokaido Line. If you are coming from the West (e.g. Osaka, Nagoya), go to Toyohashi and transfer to the Tokaido Line.
This area is famous for many Onsen and is a beautiful place to visit at any time of year. Located on Lake Hamana, this area is famous for its gates Torii The central point of the fireworks festival is in the middle of the lake.
This festival is very crowded, so it's best to arrive early and bring a blanket and a cooler full of beer and food. Find a spot on the lakeshore with a good view of the torii gate and make yourself comfortable (and maybe a little tipsy). From midday, stalls will be set up for you to enjoy Japanese festival foods, including Yakisoba, oknomiyaki, Gyoza and many other dishes. Another fun activity is to see the locals in their beautiful summer kimonos (if you go to the festival). Yukata If you arrive in Hamamatsu earlier in the day, you can pick up a set yourself!).
Alternatively, you can book a room at one of the many hotels on the lake or rent a boat and watch the fireworks on the lake. However, you have to book both in advance and it's not cheap.
Fireworks are fired from a smaller island in the lake, illuminating the torii gate. The show starts around 7:30pm (twilight) and lasts an hour and 15 minutes (so bring something to sit on). There will be a few short breaks during the show to introduce sponsors (this event is free!). The old fireworks festival was absolutely beautiful compared to the lackluster Disney district! Firecrackers come in many colors and shapes such as fish, eels and smiley faces! The festival is pretty spectacular and worth checking out.