Takamanohara (plain of high heaven) (高天原)
Takamanohara (also called Takaamahara/ Takanoamahara/ Takamagahara) is a place where Amatsu kami (god of heaven) lives in the Japanese mythology and norito (Shinto prayer) in "Kojiki" (The Records of Ancient Matters).
In contrast to Ashihara no nakatsukuni (Literally, "Central Land of Reed Plains", which refers to the human world) where people lived, and Nenokuni (Land of the Roots) and Yomi (realm of the dead) where is said to have been underground, it is said to have been located in the heavenly realms. Since ancient times, there has been a view that it was located in the real place such as Yamato, Kyushu region, Hokuriku region, or Mt. Fuji from a viewpoint of interpreting the mythology realistically.
Because the original text was written in kanbun (Sino-Japanese), it is to some extent a supposition that which readings of Chinese characters are correct.
However, in the opening line of Kojiki tells that '訓高下天云阿麻下效此,' which designates us to read the Chinese character '天' as 'ama.'
Normally, the way of reading 'Takamagahara,' which uses case particle 'ga,' is common, but it is said that this way of reading spread quite recently in the history.
Descriptions in Kojiki
At the beginning of Kojiki, the name is mentioned as a place from which gods were born in 'ametsuchi no hajime' (the beginning of heaven and earth). Then gods were born one after another, and because of the passage in which two gods of kuni-umi (the birth of [the land] of Japan) put down a pike and made islands, it seems to have been considered to exist in the clouds above the sea. When Amaterasu Omikami (The Sun Goddess) was born, she was ordered to rule Takamanohara. In the part concerning Susanoo no Mikoto (a god in the Japanese mythology), there is a description which says that many gods (Amatsu kami) lived in Takamanohara and there was a place to weave at, which gives us an impression that they led a life similar to the people. Amatsu kami suppressed Ashihara no nakatsukuni, so Ninigi, a grandchild of Amaterasu Omikami, went down from the heaven (tenson korin [descent of the heavenly grandchild]), and since then Emperors who were descendants of the grandson of the sun goddess had ruled Ashihara no nakatsukuni.
Other than Kojiki
"Nihonshoki" (Chronicles of Japan) hardly has a text which mentions Takamanohara, and it can be seen only in the fourth alternate writing and the wafu-shigo (Japanese-style posthumous name) of 'Takamanohara hironohime no sumeramikoto,' which was given to Emperor Jito along with the successive emperors in 720. "Kogo shui" (Gleanings of Old Words) mentions the name only in an oracle of tenson korin and note on norito, and among the extant fudoki (description of regional climate, culture, etc.), "Hitachi Fudoki" mentions the name only twice in the opening line.
Various theories on the location
There have been various theories on the location of Takamanohara since ancient times, and the viewpoints are quite different due to the way of interpreting the myths in Kojiki.
A theory of artificiality
It is an opinion that in the first place myths are something that were artificially created, so it is nonsense to think where Takamanohara was located. This is represented by Banto YAMAGATA's opinion, and he claimed that the age of the gods in Kojiki was artificially made by posterity. A historical view of Sokichi TSUDA, which has been the main current after WWII, was based on this idea. Today, most of the scholars agree with the opinion that a myth of Takamanohara mentioned a belief that those who belonged to the governing class were important because they were derived from the heavenly world. Although it is different in a thought, it is substantially the same as the following theory of tenjo (in the sky).
A theory of tenjo (in the sky)
It is a view that Takamanohara was a place where gods lived, so it is no doubt that the place was located in the heaven, and it was arrogant to think of a place other than this. This is represented by Norinaga MOTOORI's theory, and it was linked with Kokoku Shikan (emperor-centered historiography which is based on state Shinto) and the main current before WWII.
A theory of earth
This is a theory that myths contain some sort of historical fact so Takamanohara reflects what really existed. In today's history, such a theory is generally avoided because it is considered just a pick-and-choose attitude and not persuasive. However, such theory was often advocated during the premodern times, and still can be frequently seen in the opinions of enthusiasts.
The representative theory was advocated by Hakuseki ARAI, and he said, 'gods are human beings.'
Moreover, a theory of earth is classified into theories of the interior of Japan and foreign countries. Among the theories of the interior, some states that Yamataikoku (Yamatai Kingdom) had something to do with Takamanohara. The representative theories of foreign countries are a theory of Korean Peninsula and a theory of the southern China, which have a lot in common with a theory of Japanese people's origin. One example was advocated by Namio EGAMI, who wrote a theory of a dynasty conquered by equestrian people.
Incidentally, it is considered that Takamanohara was Katsuragi in Yamato Province by the people in the Kyoto Imperial Court until Hakuseki ARAI advocated his theory.
Takamanohara in various places in Japan
Katsuragi region, Takamadai area of Kongo-san Mountain (Takama, Gose City, Nara Prefecture)
Takama, Gose City, the southern part of Nara Prefecture. It is located on a plateau which spreads out in Mt. Kongo-san (Kongo mountainous district). In ancient times, the area was called Katsuragi, and the towering Mt. Kongo-san was said to be Takamanohara. The neighborhood is a traditional place where heavenly gods lived. Takamahiko-jinja Shrine located here is a Myojin taisha (grand shrine), which was considered the highest shrine ranking in Engi shiki (one of the earliest extant written records of imperial court etiquette compiled in the Engi era), and the enshrined deity is Takamimusubi, the founder of the Katsuragi clan. The object of worship enshrined here is Hakuunho peak (694m) at the back of the main building of the Shinto shrine. On the both sides of the approach to the shrine, old Japanese cedars stand, which provides an atmosphere of sublimity. Until the early Edo period, this place was considered historical site of Takamanohara.
Takachiho district (Takachicho-cho, Miyazaki Prefecture)
The northern part of Miyazaki Prefecture. There are Ama no iwato (cave of heaven), Ama no kaguyama hill, Takamanohara, Shiojigamine mountain, and so on. Takachiho no Yokagura (ancient Shinto music and dancing which starts in the night and ends in the morning), which is said to have begun by the dance performed by Amenouzume (goddess of entertainment), has been handed down in Takachijo-jinja Shrine.
Aso and Soyo district (Yamato-cho, Kumamoto Prefecture)
The district has 'Hi no miya/ Heitate-jingu Shrine,' which is the birthplace of the Takamanohara myth. The object of worship enshrined here is a stone slate on which Toyokuni letters and Abirumoji letters were engraved, and the back and front of it has letters 'Asohino Okami' and '日文' (literally, the sun letters).
Heitate' means himorogi (an abode of the gods), and it is considered the sacred land where the heavenly god descended in ancient times.
Hiruzen Plateau (Maniwa City, Okayama Prefecture)
It is located at the top of a mountain which belongs to the Kayabe-jinja Shrine. There are Ama no iwato, Manai no taki waterfall, Ama no Ukihashi (the heavenly floating bridge), and so on.
Oinuana (Ueno-mura, Gunma Prefecture)
It had been known as a small hole for a long time, but in 1929, a long path leading to the inner part was found. The name was derived from a discovery of many bones of wolves, and in the cave, there are places which were named Takamanohara, Ama no Yasukawa, and so on.
Taga District, Ibaraki Prefecture
A theory advocated by Hakuseki ARAI. He identified Takamanohara with Taga District, Hitachi Province, by comparison in 'Koshitsu' (a history book written by Hakuseki ARAI).