I always come here to swim in the summer. It's my favorite campsite next to Choshi River which I think is the cleanest river in Japan.

English Info: https://camp-inn-miyama.com/wp-content/uploads/2023/02/general_information.pdf

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Camp Inn Miyama is a picturesque camping spot nestled in the mountains by the sea, offering a perfect blend of nature's beauty. With clean facilities and various activities like river play and hiking tours, it's a great place to unwind and enjoy the outdoors.