Nagasaki becomes Kyushu’s party capital in early August, with the Sasebo Seaside Festival. The Festival’s main draw is the island’s largest firework display in the evening on the first day. If summer hanabi isn’t your jam (and if not, why not?), the Seaside Festival includes music, balloon art, jazz, food stalls, dance exhibitions, family games, traditional taiko drumming, and harbor cruises.
In 2017, the Sasebo Seaside Festival attracted 280,000 visitors. The main venue is an easy 5-minute walk from JR Sasebo train station, and with a packed event schedule offering something for pretty much everyone, it would be an awesome day out for kids and adults alike.