The Chikuma River Half Marathon is one of Nagano Prefectureβs premier spring running events, offering participants the opportunity to race alongside the scenic Chikuma River (Chikumagawa)βJapanβs longest river. Held in the city of Komoro, the event combines a fast, mostly flat course with sweeping views of the surrounding mountains, making it an excellent choice for runners chasing a personal best while enjoying one of central Japanβs most picturesque landscapes. Every year, thousands of runners from across Japan gather to celebrate the arrival of spring, when the riverbanks begin to come alive with fresh greenery and the snow-capped peaks of the Japanese Alps provide a spectacular backdrop.
The race is best known for its welcoming community atmosphere and outstanding volunteer support. Local residents line the course to cheer on participants, while aid stations are staffed by enthusiastic volunteers offering hydration and encouragement throughout the race. The event caters to runners of varying abilities, featuring the flagship half marathon alongside shorter distance events that allow families, beginners, and younger runners to participate. The relatively gentle elevation profile makes the half marathon especially attractive to first-time half marathoners as well as experienced athletes looking to achieve fast finishing times.
