The Marimo Festival is a traditional event held every autumn in Akanko Onsen, Kushiro, Hokkaido, and began with the purpose of protecting the "Marimo," a special natural monument of Lake Akan. Marimo are beautiful green, spherical algae that are loved by many people for their unusual shape and unique ecology. The Marimo of Lake Akan are known to grow particularly large, and their conservation efforts have attracted attention not only in Japan but also around the world. This festival is closely related to the traditional Ainu culture, and through the Ainu ritual "Kamuinomi," it is an opportunity to raise awareness of gratitude for nature and the protection of Marimo. The Marimo Festival is not just a tourist event, but a cultural event with a sense of mission to protect the natural resources of the region. A variety of programs are available during the festival, and eye-catching events such as the Marimo Dance Parade and the Torch Parade attract tourists. In addition, lectures and observation sessions are held to learn more about the ecology and habitat of Marimo, which is very beneficial as part of nature education. This festival is a valuable opportunity for local residents and tourists to come together and experience traditional culture and nature conservation. By learning about traditional Ainu culture and the Marimo ecosystem, visitors are taught the importance of coexisting with nature.