Free campsite & travelling in Japan. There are many Free and Cheap campsite in Japan. I provide information from Fukuoka in Japan.
Information of campsites are mainly Kyushu area of Japan. and it will be updated little by little.
And you will be able to find a free campsite in Japan, If you look at this website.
Usually campsite is managed office of each municipality, So I recommend that you contact the office before you use.