Hiking through the central mountains on a balmy day feels like floating in the sky above the ocean, above all of Kyushu, really. It's easy to forget the world below when hiking through the bamboo grass and rhododendrons. But hit upon a storm, and nature will remind you who rules this realm.
The miracle of Yakushima began with the formation of the highest peaks in all of Kyushu. A bubble of magma that cooled and hardened underground 15 million years ago formed a great pluton of granite that continues to rise even today. Over the eons, as the granite rose up, the covering sediment wore away to reveal Yakushima's great peaks and rock formations.
The mountains in Yakushima can be divided into the outer mountains, Mae Dake, and the central mountains, Oku Dake. The Mae Dake are the smaller mountains that local communities would traditionally use for daily needs like wood and charcoal. The central mountains, although mostly hidden from view by the Mae Dake, include the highest mountains in Kyushu, with Miyanoura Dake rising up to 1936 meters. This is the sacred heart of the island, with the inner shrine of Yaku Jinja at the peak of Miyanoura Dake.
These are the grand peaks which force the winds to rise and cool and turn wet air masses to clouds and rain. These are the peaks that create subalpine conditions similar to Hokkaido in a subtropical island and receive Japan's southernmost annual snowfall.
They are aso the peaks covered in pyroclastic flow when the nearby Kikai Caldera exploded 7,300 years ago, burning and extinguishing life in most of southern Kyushu. The red tephra known as Akahoya is still visible in some places at lower elevations.
And if you wander down to the coasts, in many places you'll see the folds of sediment from the Phillipine Plate that have been scraped off by the Eurasian Plate (where Yakushima is located) and that have buckled under the pressure and been brought to the surface as Yakushima rose up above the ocean.
Domain of the Gods
In a land so dominated by mountains, it is no wonder that the Japanese god of mountain fortune, Yamasachihiko, plays such a large role in local religion. There are close to 30 mountain shrines dedicated to this god, marked by blocks often inscribed with the Buddhist name, Ippon Hoju, and hauled up the slopes. Traditionally, each village around the island would send an envoy of pilgrims to the nearby Mae Dake and to the central Oku Dake. Though these traditions waned in the 20th century, they are now experiencing a rennosance of interest in various villages.