The festival is called Defune Matsuri Festival, every year it is held on 24th July, so excuse me but I'm going to use my old blog post from the past years to describe the festival here because the festival is the same, nothing change for years.
The festival run between 19:30 to 20:45.
It is a traditional story play in open-air and the stage will be on the sea and the bridge.
Story is; There was a bad dragon in Tango region's sea in the past and Monju-Bosatsu god who alter the dragon to good one! ;) So that's what you will see in the play. You don't need to understand language because it is a non-verbal play, only music.
In the first 30mins, children will dance with Taiko drums, they are usually very cute to see.
Chion-ji temple area&the first bridge to Amanohashidate sandbar(near by station side) will be lighted up with bonfire. Around 20:40-21:00 you can also watch small fireworks.
Access: 3mins walk from Amanohashidate station
Free admission.