Takachiho is the site of one of the best known legends of Japanese mythology. In the story, Amaterasu, the Shinto sun goddess, became so outraged by her brother's cruel pranks that she hid herself in a cave, refusing to come out and depriving the world of her life-giving light.
All of the other gods and goddesses gathered to lure her out. They tried everything they could think of to no avail until one goddess performed an outrageously ribald dance that caused the other gods to roar with laughter. Amaterasu left the cave to see what all the fun was about, and in doing so she returned her light to the world.
About ten kilometers outside of central Takachiho, Amano Iwato Shrine (天岩戸神社, Amano Iwato Jinja) was built near the cave where Amaterasu is said to have hid herself away. The shrine's main buildings are located on the opposite side of the Iwato River from the cave.
The cave cannot be approached, however, there is an observation deck behind the shrine's main building from where you can gaze across the river. In order to access the observation deck, you need to inquire at the shrine entrance, and a priest will give you a guided tour in Japanese.
A short walk down the road from Amano Iwato Shrine is a path that leads down to the river below. After a few minutes on this path you will see neat little piles of stones stacked along the river by previous visitors to mark their pilgrimage to this "power spot". Farther along, the stacks become more numerous until you are surrounded by literally thousands of them as far as you can see.
Eventually the path leads to a simple shrine inside a cave known as Amano Yasukawara (天安河原). This is said to be the cave where the gods and goddesses met to discuss their strategy of luring Amaterasu out of hiding. The natural beauty of the cave and river lined by countless stacks of stones make Amano Yasukawara a place not to miss.
Amano Iwato Shrine stands ten kilometers outside of central Takachiho. A bus operates between the Takachiho Bus Center and the shrine (15 minutes, 300 yen one way, one bus every 1-2 hours). Alternatively, a taxi ride costs about 2500 yen one way.
Amano Yasukawara is about a ten minute walk from Amano Iwato Shrine. Follow the road for a few meters until a path leads down to and along the river to the cave.