第15回 千葉南房総アクアスロン大会 2026

The Chiba Minami Boso Aquathlon, a swim-run race, takes place at Iwai Beach in Minami Boso City, Chiba Prefecture, close to the west-side parking area. It occurs in June, with competition running from morning until early afternoon. This marks the event's 15th year. Participants can choose a short course (500 m swim, 5 km run) or a long course (1500 m swim, 10 km run). A 1500 m swim-only option and a relay event, where one person swims and another runs, are also available. Time limits are set at 20 minutes for the short swim, 40 minutes for the short run, 50 minutes for the long swim, 70 minutes for the long run, and 120 minutes total for the relay. Entry fees vary by category, with reduced rates for P/G members and a surcharge for late registrations.