Rock Festival Calendar for September [2025–2026]

The Gunma Rock Festival, which was held for three years starting in 2011, has been reborn as “Yamabito Ongakusai.” The central driving force behind the event is G-FREAK FACTORY, and the title “Yamabito” (mountain folk) was chosen to evoke Gunma Prefecture’s mountains: Mt. Akagi, Mt. Haruna, and Mt. Myogi.

Set in Iwamuro, a hot spring area in Niigata Prefecture, this music event invites everyone to share what they love and enjoy, and to express it freely. Aiming to share the joy of spending time in the countryside, we bring out each person’s unique color, freely paint the space called Iwamuro, and share that time together by creating the event as one. Why not shift from spending your days just going into town to shop and coming home tired, to a way of living where you create your own enjoyment right in the town you call home?

Master Colosseum—aka Masukoro. The original festival of sound by bands, for bands! It’s an outdoor live event where the real thrill is the skirmishes between rival acts. It’s grown bigger every year, and we deliver a more robust lineup than ever.