第20回真鶴・岩海岸 オープンウォータースイミング大会 2026

At Iwa Beach on the Manazuru Peninsula, this open-water swim feels like a small coastal day out rather than a race. The beach is described as a “quiet, clean beach that is easy to swim at,” and this 20th edition takes place on a shore also famous as the spot where Minamoto no Yoritomo set sail. The venue is “the only sandy beach on the Manazuru Peninsula,” tucked into an inlet, so the waves are relatively calm. That makes it a gentler setup for swimmers and a nice one for families with small children, with the main draw being simple: getting in clear, manageable water off a beach with a bit of history.