Akiyoshidai Karst Plateau (秋吉台) 秋吉台
The limestone was born as a coral atoll 350 million years ago: the plate carried it here.
Quasi-national park since 1955, with 1,269 hectares of the eastern side (beyond the Kotō River) protected as a special natural monument since 10 July 1964. The designation came after the area risked becoming an air and naval training range in 1956: local opposition saved it. Beneath the grassland lie more than 400 recorded caves, including Akiyoshidō.
Yamaguchi
秋吉台