Monograph No. 16

NARA IMPERIAL PALACE ARCHAEOLOGICAL SURVEYS CARRIED OUT IN 1960－1962（1963）

CONTENTS

ChapterⅠ. Introduction　1

Chaptcr II. Plan of Investigation　4

1.Outline　4

2. Plan of Excavations　5

3. Diary of Excavations　７

Chapter III. Sites　10

1. Survey of Sites　10

2. Structural Remains　13

3. Dating of Remains　21

4. Investigation of Area 6AAO-T・U　23

Chapter IV. Artifacts　26

1.Tiles　26

2. Earthenware &c.　28

Chapter V. Inner Court of Heian Palace　30

1. Old Maps and Plans of lnner Court of Heian Palace　30

2. The Problem of the Inner Court of the Heian Palace　38

Chapter VI. Specific Questions　45

1.Documentary Evidence Concerning Inner Court of Nara Palace　45

2.Structural Remins　50

3.Artifacts　64

4.Conclusions　66

TABLE: 1. Chronological Table of Nara Imperial Palace　71

2.Classification of Roof-tiles　87

English Summary　ⅷ

NARA IMPERIAL PALACE

　The present report is a summary of the results of the 3rd, 6th, and 9th surveys of the Nara Imperial Palace site, carried out in 1960, 1961 and 1962, respectively, by the staff of the Nara National Research Institute of Cultural Properties.　The excavated area is situated at Saki-cho in Nara, and is at the northern end of the Government-owned site.　The existence of some structural remains in this area was discovered in 1924, when in the course of landscape improvement some small pillar base stones were unearthed at the northeastern and southwestern ends of this area, suggesting that some rather important buildings once had been erected there, although their nature and function were then unknown.
　The three successive surveys summarised in this report made it clear that the area tentatively termed 6AAQ and its neighbour, 6AAP, were once the Inner Court, or Imperial domicile, in the latter half of the 8th century.　This Inner Court was almost a perfect square in shape, about three hectares, enclosed by a corridor.　To be precise, the corridor is 176.9m. in length from east to west and 185.3 m. from north to south.　The corridor had a thick earthen wall in its center, 1.4 m. wide at the base.　On either side of this wall, pillars were erected in rows, each at a distance of 3.17 m. from the center line, supporting the roof covering the passageways beneath.　The central earthen wall was reinforced by suitably spaced buttress pillars that stood on base stones 45 cm. square.　The floor of the corridor was paved with square dressed slabs, and conduits were made of dressed stones as well.　The platform of a gate was found on the eastern wing of the corridor, and a sill stone for the door also came to light.
　In the southern part of this square court, excavation laid bare an inner quarter enclosed with a corridor of simpler construction whose roof was supported by inserted pillars.　The supreme hall and annex were discovered there, the former being situated north of the center of the enclosure and the annex east of it.　The supreme hall corresponds to what was later called the Shishin-den in the Heian Palace, and has been maintained by tradition to the present day as the main edifice of the Kyoto Palace.　The present supreme hall is thatched with cypress bark, and the total absence of roof-tiles in the site seems to indicate that its remote predecessor was also thatched with similar perishable material.
　The structural remains uncovered in Area 6AAQ show five successive chronological layers, the most important being the fourth stage, which includes the inner court buildings.　The remains from the 1st to the 3rd layers are fences and lesser structures, whose functions can no longer be surmised.　The material evidence, such as roof-tiles used on buildings other than the supreme hall and potsherds recovered from conduits in corridors, indicate that the Inner Court was erected between 745 and 764 A.D, and was in use until the end of the Nara Period.　In our previous report, the chronological sequence of the structure and other remains then found was summarised in a table, showing five successive stages.　By applying this method to the present surverys, it was found that the Inner Court was built in stage Ⅱ-1 and existed until stage Ⅱ-3 of our tentative chronology.
　An interesting by-product of the present surveys is the finding of a tumulus of key-hole shape, 100 m. long, which once existed at the southeast end of the supreme hall of the Inner Court.　The discovery was made partly by excavation and partly by electrical computation.　The tumulus was completely destroved by the construction of the capital, as well as another larger tumulus, also key-hole shaped, 250 m. long, whose rear round mound is now said to be the tomb of Emperor Heizei, and whose southern end extended into Area 6AAO.
The discovery of these demolished mounds bears eloquent corroborative testimony to the Imperial Edict issued in the tenth month of 709 A.D., to the effect that ceremonies should be conducted to soothe the spirits of the dead whose burial places were to be destroyed by the erection of the new capital.