Sakai Katsutoki published a book, The Pyramids of Japan, in 1934. Here is his list of 12 pyramid mountains.
- 葦嶽山／広島県 Ashitake Yama, Hiroshima
- 尖山／富山県 Togari yama, Toyama
- 位山／岐阜県 Kuraiyama, Gifu
- 五葉山／岩手県 Goyosan, Iwate
- 大石神／青森県 Oishigami, Aomori
- 黒又山／秋田県 Kuromanta yama, Akita
- 三瓶山／島根県 Sanbin yama, Shimane
- 剣山／徳島県 Tsurugi san, Tokushima
- 日室ガ嶽／京都府 Himurogatake, Kyoto fu
- 皆神山／長野県 Minakami yama, Nagano
- 千貫森／福島県 Sengan mori, Fukushima
- 八幡山／兵庫県 Hachiman yama, Hyogo
A Japanese pyramid is said to have three characteristics.
1. It is triangular in profile. While Egyptian and Mayan pyramids have square bases, Japanese pyramids usually have a circular base although there are square ones as well.
2. At the mountain peak are iwakura, rock seats where kami are said to descend. These are not only large stones, they are megaliths. They may be arranged in different ways. For example, some are menhirs, others are table-formed, others are stone circles.
3. Since the iwakura are sacred, there is usually a worship location to pray to the kami of the mountain.
We believe that before there was Shinto, or even Koshinto, the spiritual practice of the ancient people was to connect with the universe on mountaintops. Later, when shrine building were erected, they were situated with certain alignments, east-west being a favored one. Also favored were solsticial alignments. At the latitudes of the archipelago, the directions would have been 30 degrees north and south of east.