The 6,700-hectare Sarobetsu Marsh, which stretches across the Sea of Japan side of northern Hokkaido (Toyotomi Town and Horonobe Town), is larger than the inside of the JR Yamanote Line and is one of the three largest wetlands in Japan. It is one of the three largest marshlands in Japan. In particular, it is the largest high-altitude marshland in Japan with well-developed mosses, and is designated as "Rishiri Rebun Sarobetsu National Park".

At the Sarobetsu Marshland Center, an information facility located at the entrance of the marshland, visitors can learn about the formation of the marshland and its natural features through photo panels and videos. Visitors can enjoy the magnificent nature of Sarobetsu by walking along the 1 km barrier-free wooden path that circles the marshland.