Heijō Palace

The Suzaku Gate is the main entrance to the palace

The main entrance to the capital through the Suzaku Avenue was the Rajō Gate (羅城門, Rajōmon). The main avenue was approximately 75 metres (246 ft) wide and extended north for 3.7 kilometres (2.3 mi) up to the Suzaku Gate (朱雀門, Suzakumon). The name "Suzaku" derives from the Chinese name for the legendary bird which acted as a southern guardian. The palace was surrounded by great earthen walls and had twelve gates, with the Suzaku Gate as the largest gate and the main entrance. The southern open spaces was part of the main avenue, and the Nijo Oji (二条大路, Nijō-Ōji), the second great street, approximately 37 metres (121 ft) wide was extending in the east-west direction in front of the gate.

The gate measured 10 by 25 by 22 metres (33 ft × 82 ft × 72 ft). Built on a platform, the gate was probably a two-storied structure, conspicuously larger than the other gates of the palace. The open space to the front was used for ceremonies such as New Year celebrations. It was reconstructed in 1998.

The Second Street was a major thoroughfare running east-west along the southern side of the palace precinct. Around 35 metres in width, it was second only to Suzaku Avenue in size. The Suzaku Gate, which was the main gate, together with the Mibu Gate to its east and the Wakainukai Gate to its west, all opened onto this avenue.

In the latter half of the Nara period, the Great Hall of State and the Halls of State compound that comprised the centre of politics shifted to the eastern sector of the precinct. The Mibu Gate served in effect as the main gate to the palace.

The area immediately to the south of the Second street is known to have been used for state offices and detached residences located outside the palace grounds, and was thus a district rivaling the palace itself in importance.

The daidairi was a walled rectangular area extending from north to south between the first and second major east-west avenues and from west to east between the north-south avenues.

The three main structures within the Greater Palace were the Official Compound (朝堂院, Chōdō-in) and the Inner Palace (内裏, Dairi).

The Chōdō-in was a rectangular walled enclosure situated directly to the north of the Suzaku Gate in the centre of the southern wall of the Greater Palace. It was based on Chinese models and followed Chinese architectural styles, and archaeological evidence from earlier capitals shows that this building complex was present in earlier palaces and had a remarkably stable design from the 7th century onwards.

The Great Hall of State

The Takamikura throne in the Great Hall of State

The Great Hall of State (大極殿, Daigokuden) was the most important state building in the palace. It was facing south at the northern end of the compound. It was the largest building, measuring 20 by 44 by 27 metres (66 ft × 144 ft × 89 ft) 44 metres in width and 20 metres in depth, with a height of 27 metres. The hall was thought to have been a two-storey Chinese-style structure with a hipped and gabled roof, and an open front façade having no doors.

No data directly indicating the audience hall's true appearance have survived. For the reconstruction, locations of the pillars were inferred through reference to the building's remains at Kuni-kyō, to where it had been relocated. For the upper part of the building, research was conducted on the main hall of Hōryū-ji, the eastern pagoda of Yakushi-ji, and other buildings that survived from the Nara period. The depiction of the Heian Palace audience hall depicted in the Nenchu gyoji emaki (Illustrated scroll of annual events and ceremonies) was also consulted.

The reconstruction was started in 2001 and completed in 2010. For the reconstruction, Japanese cypress wood was used. The building's pillars and beams were painted in vermilion, the walls in white, the roof with ceramic tiles. The upper part of the interior of the hall was painted with symbols of the Chinese zodiac such as the Tiger, the Horse and the Ox alongside the walls, and floral pattern on the ceiling. The paintings were executed by the renowned painter Atsushi Uemura based on designs from the Nara period.[6][7]

In the middle of the audience hall was the emperor's throne, called Takamikura (高御座). This was an important item that symbolised the imperial office, and at state events such as the enthronement and New Year's Day ceremonies the emperor proceeded to the audience hall and took his seat on the throne. Nobles lined up in the inner court south of the hall and paid their respect.

With no records of the construction or design of the Takamikura of the Nara period, the details are unknown. The reconstructed model of the Takamikura was made after experts consulted various literature and historical materials, and based on the throne in the Kyoto Imperial Palace which dates to the Taishō era. Details of the design and patterns were created by referring to materials such as the treasure of the Shōsōin repository.

This area, stretching northward from the centrally located Great Hall of State, is believed to have been the site of the Office of Foods. This office stocked foods other than the rice that was paid as tax, and was in charge of providing meals for state banquets and rituals held in the palace.

Surrounding a large well, itself provided with a roof and from which numerous eating utensils have been excavated, stood a group of buildings used as offices and storehouses. The first inscribed wooden tablet recovered from the palace site was found in 1961 in a rubbish pit belonging to this office.

The latter audience hall dates to the time after the capital was re-established after the relocation from Shigaraki.

Traces of the platforms of the latter audience hall and the eastern state halls had remained by the Meiji era, which led to the discovery of the site by Sekino Tadashi, a researcher of architecture history. Tanada Kajuro, a local gardener, worked on a public movement for protection of the site.

The area on the north side of the latter audience hall is the site of the imperial domicile.

The emperor and empress lived, worked, and received visitors in the imperial domicile section. It was surrounded by a roofed walkway, divided lengthwise by an earthen wall. The Office of the Court Ladies was also located here.

Inside the imperial domicile was a stone-paved area containing a large well, which remains were found in 1973. The well was lined with a solid cedar tube carved from a log 1.7 metres (5 ft 7 in) in diameter. The water from this well was probably for the exclusive use of the emperor and empress. The site was reburied and the wall was reconstructed with new materials as an outdoor exhibit.

In this section to the east of the imperial domicile, is what is thought to have been the Office of the Imperial Household (宮内省, Kunai-shō). It was surrounded by an earthen wall, 90 metres in length to the north and south and 50 metres wide from east to west. Six buildings stood in this compound. The main one was roofed with tiles, the others with cypress bark.

The building were reconstructed in accordance with the findings of the archaeological excavations, following the Nara period construction techniques.

The East Palace Garden

Archaeological excavations uncovered remains of a large garden in the southeast corner of the palace in 1967. This was named "East Palace Garden" (Tōin Teien) because the neighbouring area is considered to be the site of the East Palace.

Within the area measuring 100 by 80 metres (330 by 260 ft). Several buildings were located around a curvilinear pond. In the vicinity of the site, Empress Shōtoku had the "Jewelled Hall of the East Palace" constructed, in which banquets were held.

The excavations revealed that the garden was originally built in the Chinese style of the early Nara period, and modified in a Japanese style of the late Nara period. The garden was reconstructed in 1998.