Creation of Shimane: Geography
Shimane Prefecture is the setting for many of Japan’s earliest myths, and its landscape retains the scenic beauty that inspired those ancient stories. Around 78 percent of the prefecture is forest, and much of the remaining area comprises Lake Shinji and Lake Nakaumi. The wetlands surrounding these lakes act as crucial habitats for some 50,000 migratory waterfowl, and in 2005, roughly 8,000 hectares around Lake Shinji and 9,200 around Lake Nakaumi were designated protected sites under the Ramsar Convention, an international treaty for wetland conservation.
Northern Shimane lies along the Sea of Japan, where rough winds and waves have carved an intricate coastal profile. Particularly along the Shimane Peninsula, sea caves, grottos, and islets weathered into dramatic shapes dot the shoreline. Along the Koizu Coast, fossil-studded cliffs and a coastal bench of eroded turbidite reveal part of a sea floor that formed 15 million years ago.
Most of Shimane Prefecture is hilly or mountainous, with river-carved canyons and steep, rocky ravines. Two of these, Tachikue Gorge and Oni no Shitaburui, were named National Natural Monuments in 1927 and designated as prefectural nature parks in 1964. Tachikue Gorge, formed by the Kando River, is a 2-kilometer stretch of towering andesite cliffs ranging from 100 to 200 meters tall. Oni no Shitaburui is a 3-kilometer ravine whose riverbed is filled with massive boulders that create plunging rapids.