Nagaoka-kyo (Nagaokakyo) (長岡京)

Nagaoka-kyo
Nagaoka-kyo was an imperial capital that existed in Otokuni no Kori, Yamashiro Province from 784 to 794. The old capital corresponds to the present-day Muko City, Nagaokakyo City and Saikyo Ward in Kyoto City, Kyoto Prefecture. This will be discussed in the following section.

Nagaokakyo City, Kyoto Prefecture
The name of Nagaokakyo City originated from Nagaoka-kyo mentioned above because the area of the city partly corresponds to the old capital. Although it had been called Nagaoka-cho, Otokuni-gun before city status was granted, the city was named Nagaokakyo City because the city named 'Nagaoka City' already existed in Niigata Prefecture.

Nagaokakyo Station: A station on the Tokaido Main Line (JR Kyoto Line) of West Japan Railway Company (JR West) in Nagaokakyo City.

Nagaoka-kyo was established in 784 when Emperor Kanmu transferred the capital from Heijo-kyo to Nagaoka-kyo. It is interesting to know that the year 784 was the year of the Kasshi kakurei (the first year of the sixty-year cycle in Chinese calendar when changes are often said to happen), and that Emperor Kanmu was a direct descendant of Emperor Tenchi, not of Emperor Tenmu.

The 'Shoku Nihongi' (historical books written in the Heian period) describes the reason for the transfer of the capital as easy access to water and land transportation; however,
it is also said that, distancing the capital from the established groups of Buddhist monks and nobles,
a relationship with the immigrants ruling the regions around the new capital, who had a common ancestry with Emperor Kanmu's mother,
and a transformation caused by a shift of the imperial line to Emperor Tenchi's from the reign of his father, Emperor Konin
are also reasons for the transfer.

In 785, a 'zo-nagaoka-kyo-shi' (造長岡京使) (one of the extra statutory officers who was in charge of building Nagaoka-kyo), FUJIWARA no Tanetsugu was murdered, and Emperor Kanmu's kotaitei (brother and the first heir to the throne), Imperial Prince Sawara became a suspect and was banished. Imperial Prince Sawara passed away harboring a grudge, and this became the basis for rumors of his ghost. After a short period of ten years, the capital was transferred again to Heian-kyo in 794.

Rivers, the main means transportation in the capital, were often flooded.

Misfortunes, such as the natural disaster mentioned above, an epidemic, and the empress's and imperial prince's illness, were said to be caused by Imperial Prince Sawara's ghost.

These occurrences are said to be the cause of the transfer of the capital.

Nagaoka-kyo had been called the 'phantom capital' until recently, but members led by Shuichi NAKAYAMA, a high school teacher, began to excavate the area in 1954, and the following year, they found the site of the gate of the Daidairi Chodoin (a large hall at the front in the palace); more excavation and research have been done to date (partly because research on the land has been required to meet the increased demand of land for industrial use and housing), and the site has been designated as a National Historical Site since 1964.
As a result of these excavation, the following findings were made:

Contrary to popular belief that the Nagaoka-kyo was unfinished and abandoned, the construction of Nagaoka-kyo was nearly complete, as shown in the reconstruction of not only the old palaces such as Naniwa no Miya but also the buildings in Heijo-kyo.

Nagaoka-kyo was about the size of Heian-kyo or Heijo-kyo.

Some believe that the transfer of the capital to Nagaoka-kyo was a token gesture due to the short period of time, and that the main purpose of the transfer was to prepare for the major transfer and thus it was a practice of 'kata-tagae' ('changing directions' according to Japanese esoteric cosmology 'Onmyodo').