Shonan International Marathon

Shonan International Marathon is one of Japan’s most distinctive seaside marathons, held in the Shonan coastal area of Kanagawa, Japan, with Oiso serving as its central host location. Known for its long, flat course and sweeping ocean views, the race gives runners a rare chance to run along the Pacific coast with Mount Fuji often visible in the distance. Unlike dense urban marathons, the event stands out for its open coastal setting, broad roads, and destination-race feel, while still being easily accessible from the Tokyo area. With marathon and shorter distance options, it has built a reputation as a memorable late-year race that blends competitive potential with scenic appeal and a strong regional identity.