Heian-kyō
Heian-kyō (平安京?, literally "tranquility and peace capital") was one of several former names for the city now known as Kyoto. It was the capital of Japan for over one thousand years, from 794 to 1868 with an interruption in 1180.
Emperor Kanmu established it as the capital in 794, moving the Imperial Court there from nearby Nagaoka-kyō at the recommendation of his advisor Wake no Kiyomaro and marking the beginning of the Heian period of Japanese history. The city was modelled after the Tang dynasty Chinese capital of Chang'an (modern-day Xi'an). It remained the chief political center until 1185, when the samurai Minamoto clan defeated the Taira clan in the Genpei War, moving administration of national affairs to Kamakura and establishing the Kamakura shogunate.
Though political power would be wielded by the samurai class over the course of three different shogunates, Heian remained the site of the Imperial Court and seat of Imperial power, and thus remained the official capital. In fact, even after the seat of Imperial power was moved to Tokyo in 1868, since there is no law which makes Tokyo the capital, there is a view that Kyoto legally or officially remains the capital even today.
In 1994, Kyoto City held various events commemorating the 1200th anniversary.
Heian-kyō was built in what is now the central part of Kyoto city covering an area spanning the Kadono ( Kadono-gun?) and Otagi Districts ( Otagi-gun?) of Yamashiro Province. The city boundaries formed a rectangle measuring 4.5 km from east to west and 5.2 km from north to south. The city layout followed Heijō-kyō (Japan’s capital during the Nara period) with the Imperial palace, Daidairi, placed in the centre of the northern city limits and the Suzaku Avenue (Suzaku-ōji), the main thoroughfare extending from the palace down through the centre of the city, dividing it into the Right (Ukyō) and Left Capitals (Sakyō) (the eastern side being the Left and the western side being the Right from the emperor's viewpoint.) The design followed Sui and Tang dynasty Changan with the exception that Heian-kyō had no city walls. It is thought that the site for the city was selected according to the principles of Shijinsōō (?, "Four Gods Suitability") based on Chinese Feng shui and relating to the Four Symbols of Chinese astrology.
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