Ota City Peace Fireworks Festival (大田区平和都市宣言記念事業) is a fireworks event held along the Tama River, typically on 15 August each year. About 5,000 fireworks are launched, making it one of the smaller firework events in Tokyo, but there is also a main stage with some musical performances beforehand.
Event details are taken from official sources whenever possible. It is always prudent to check the official event website before attending to make sure that there have not been any changes. If you know of an error in the calendar, then please let me know through the contact form.