Monograph No. 34
NARA HEIJO IMPERIAL PALACE SITE EXCAVATION REPORT IX
SURVEYS IN AREAS OF OUTER GATES AND SURROUNDING WALLS
CONTENTS
Page
Chapter I. Introduction 1
Chapter II. Progress of Research Work 4
1. General Description of Research Work 4
2. Daily Record of Excavation Work and Events 7
A. Survey 14 7
B. Survey 15 8
C. Surveys 16 and 17 9
D. Survey 18 11
E. Survey 23 12
F. Survey 25 13
G. Survey 25-2 15
H. Survey 34 15
I. Survey 52-2 16
J. Survey 58 16
K. Survey 62 16
Chapter III. Excavated Sites 17
1. Introductory Remarks on Excavated Sites 17
2. Description of Structural Remains 18
A. Area of Suzaku-mon (6ABX, 6ABY) 18
B. Area of Tamate-mon (6ADF) 21
C. Area of Saeki-mon (6ADD, 6ADE) 24
D. Area of southwest corner of palace precinct (6ADH) 27
E. Area between Tamate-mon and Saeki-mon (6ADE, 6ADF) 31
F. Area of surrounding wall on north side (6ABA, 6ABN) 32
G. Other areas 33
Chapter IV. Artifacts 34
1. Wooden Tablets (Mokkan) 34
A. Mokkan from SD1900 34
B. Mokkan from SK1979 37
2. Tiles 39
A. Round roof-edge tiles (noki marugawara) 40
B. Curved roof-edge tiles (noki hiragawara) 46
C. Tiles used as tools 52
D. Round and curved roof tiles 52
E. Tiles bearing Chinese characters 53
3. Earthenware 54
A. Earthenware from SD1900 54
B. Pottery with Ink Writings 60
C. Earthenware from other sites 60
D. Pottery from Cultural Layers･Inkstones 61
E. An Earthenware coffin 61
4. Wooden Manufactures 62
A. Wooden shields from SE1230 62
B. Wooden manufactures from SD1900 66
C. Wooden manufactures from SK1979 71
D. Wooden manufactures from other sites 76
5. Manufactures of Metal and Stone 78
A. Manufactures of Metal from SK1979 78
B. Manufactures of Metal and Stone from other sites 79
Chapter V. Interpretive Essays 80
1. Sites 80
A. Outer palace gates 80
B. Surrounding wall 82
C. Thoroughfares within palace precinct 84
D. Shaku measurement units used in palace construction 85
2. Artifacts 88
A. Tiles 88
B. Earthenware 92
3 Outer Gates and Surrounding Wall in Literature 96
4. Conclusions 99
Chapter VI. Model Reconstructions 100
1. Suzaku-mon 101
2. West-facing Gates 105
Supplementary Tables 107
Summary 115
Plans and Sections
Plates
NARA (HEIJO) IMPERIAL PALACE SITE EXCAVATION REPORT IX
Heijo-kyu (Nara-no-miya), whose construction was begun in 708, was built in the cental part of the northern extremity of Heijo-kyo (Nara), which was the capital of the country during the Nara Period, following the removal of the capital from Fujiwara-kyo in 710. The basic palace area was approximately 1250 meters from east to west and 1000 meters from north to south, but it had a protruding addition on the east side measuring 250 meters from- east to west and 750 meters from north to south. The total area was approximately 120 hectares.
With the exception of certain areas along the northern and eastern edges which are occupied by private residences, nearly the whole area of the Heijo-kyu has been preserved, and excavation surveys are continuing to be carried out. Ever, since the studies of Heijo-kyu made by Kitaura Sadamasa in the middle of the 19th century, the area of the palace was thought to be one kilometer square, and this became a fixed view in academic circles. When in 1961 a certain private company planned to develop the southwestern part of the palace area and as a result the decision was taken to preserve the entire palace site, it still seemed natural that the area in question should be taken as measuring one kilometer square. However, after excavations were begun in 1964 to determine the four sides of the palace area, it was learned that no remains existed for the three gates on the eastern side (i.e., the Yama-mon 山門, the Takerube- mon 建部門, and the Ikuha-mon 的門, from north to south, respectively) at the sites that had been postulated for them During a 1967 survey of a newly postulated site for the southernmost gate on the eastern site, remains were uncovered of a gate which opened, rather, to the south along the street known as Higashi Ichibo-oji. In this way it could be hypothesized that the Heijo-kyu had a protrusion on the eastern side of the originally supposed area. From visible topographical features of nearby paddy fields it was newly postulated that the eastern edge of the protruding area lay some 250 meters away from the originally supposed boundary. Through a 1968 survey, the southeast corner of the protruding area could be verified. This area was later designated as corresponding to mentioned in historical literature the “Toin” 東院(or ”eastern courtyard”) and thus also as the area where the Yamamomo-no-miya 楊梅宮 (“willow and plum palace”) must have stood.
The preservation of this protruding area came to be a new problem as a result. Through the efforts of many different parties, nearly the entire sector with the exception of areas where private houses already stood is to be preserved in perpetuity.
Three gates opened on each side of the rectangular palace area, and with each gate there was associated the name of a prominent clan. The gate at the center of the South side of the palace is in historical literature of the Nara Period known as the Suzaku-mon (not indicating the name of a clan), but it is possible that this gate was at first also known as the Otomo-mon. The problem of which names may be attributed to which gates was taken up in the Nara Imperial Palace Site Excavation Report II.
With the above sort of background to the various excavation surveys carried out, the present report deals with some of the areas surveyed in the attempts, mentioned above, to determine the outer boundaries of the palace precincts. The areas discussed in the present report are primarily the following: area of the central gate on the south side (the Suzakumon, Surveys 16 and 17); area of the southern gate on the west side (the Tamate-mon 玉手門, Survey 15); area of the central gate on the west side (the Saeki-mon 佐伯門, Survey 25); area of the southwest corner (Surveyl4); area between the Tamate-mon and the Saeki-mon (Survey 18); and area of the surrounding wall on the north side (Survey 23) (See Chapter I).
The southwest corner and the Tamate-mon areas were excavated in 1963; the areas of the Suzaku -mon, of the surrounding wall on the north side and of the interval between the Tamate-mon and the Saeki-mon in 1964; and the area of the Saeki-mon in 1965. The survey in the Suzaku-mon area uncovered drainage ditches on the east and west sides of the Shimotsumichi, (The three official roads “kando” which cut across the Yamato basin from north to south were called Kamitsumichi , Nakatsumichi, and shimotsumichi, respectively, the last named lying furthest to the west among the three) the road which may be taken as having formed the standard axis dividing the main area of the palace into east and west sectors at the time of the palace construction (See Chapter II/1).
In the present report, following the above-mentioned general outline is a daily record of progress in the excavation work (Chapter II/2).
Chapter III deals with the various remains uncovered.
Numbers of the various types of remains uncovered are as follows: Buildings (22); Surrounding walls (3); Other walls (22); Drainage ditches (15); wells (14); Pits (10). Remains of buildings were few due to the fact that the areas surveyed were adjacent to the outer wall surrounding the palace. The various remains are discussed in the following order: the Suzaku-mon area; the Tamate-mon area; the Saeki-mon area; area of southwest corner; area between the Tamate-mon and the Saeki-mon; area of the surrounding wall on the north side; and lastly, other small-scale excavation areas (Chapter III/1).
Among the excavated remains, we may state regarding the palace gates and surrounding wall (i.e., the principal objects of the surveys), as follows. The site of the Suzaku-mon (SB1800), in comparison to the other two gates, was in a relatively good state of preservation. The remains of the foundation stones which had been removed revealed an east-west dimension of 5span and a north south dimension of 1 span, with each span (distance between centers of foundation stones) measuring 5.05 meters. The southern half of the gate’s foundation structure had at some time been destroyed in the digging of a pond. The southernmost remaining traces of a row of foundation stones corresponds to the center line, widthwise, of the southern surrounding wall, a fact which permits us to assign two span instead of one span as the original width of the gate. No remains of other structures outside the gate’s foundation platform were revealed. When the foundation was built, it was placed largely below the original ground level but also protruded above the original ground level in the form of an earth mound specially prepared to have sufficient soil resistance. The original work of digging an excavation in the surrounding soil is known as horikomi jigyo. From the traces of this horikomi jigyo it is possible to estimate that the foundation extended 1.5 meters below the original ground level. The foundation was built up by a process known as hanchiku, i. e., successively building up and hardening thin layers o clay and sand in the area dug out to be filled. The horizontal dimensions of the gate were thus 25.24 meters in length by 10.10 meters in width (with 5.05 meters, or 17 shaku, as the distance between pillars). At approximately 29 meters to both the east and west of the gate are remains of side gate (wakimon, SB1801 and SB1802) which form openings in the southern surrounding wall of the palace. These are approximately 4 meters wide. The excavation surveys confirmed the fact that southern surrounding wall (SA1200) was built on a foundation which was set, by means of horikome jigyo, approximately 0.4 meters below the original ground level, and also the fact that the width of its base was 2.4 meters. It was possible to confirm the same base width also in the survey (No. 14) carried out in the area of the palace precinct’s southwest corner. However, within 12 meters on both the east and west side of the Suzuka-mon, the base width of the surrounding wall is found to measure approximately 3.5 meters. This feature of the surrounding wall being built wider than usual in segments which adjoin either side of a gate has not been found in the surveyed areas around other palace gates, and is thus peculiar to the Suzaku-mon. There are remains of an east-west mud (SA1812) built around posts sunk into the ground (hottate-bashira). It was constructed across the northern edge of the gate’s foundation platform, evidently after the time when the Suzaku-mon was dismantled.
In the case of the Tamate-mon (SB1616), no traces remained of the foundation stones or of the sites of their removal but the survey work revealed the position of the bottom layer of the gate’s foundation work, which had been, at the time of the gate's construction, the bottom of the area dug out through horikomi jigyo. The depth of the horikomi jigyo was discovered to be approximately 0.6 meters. The foundation was built up by means of hanchiku, as described above. As for the horizontal dimensions of the horikomi jigyo, the length was found to be approximately 32.1 meters (north to south), while a reconstructed figure for the width (only a half of which was confirmed during the survey in question) may be given as 13.9 meters.
The site of the Saeki-mon (SB3600), like that of the Tamate-mon, leaves no traces of foundation stones or their removal sites. Its size likewise has come to be known only through the remaining evidence of the horikomi jigyo, seen to have a depth of approximately 0.7 meters. The length of the area of the horikomi jigyo is 29.4 meters (north to south), while the width (east to west ) is thought to be about the same (13.9 meters) as the width of the Tamate-mon.
The surrounding wall on the palace precint’s west side (SA1600) into which the two above-mentioned gates are built, was found to have a foundation built with a shallow horikomi jigyo, in a way similar to the construction of the surrounding wall on the south side (SA1200). A reconstructed figure for the width of the foundation's base yields 2.4 meters, the same as in the case of the southern wall. A part of the remains of the northern surrounding wall was revealed in Survey 23. At the time it was built, the Heijo palace was first set apart by means of a wall of hottate-bashira construction, which was subsequently replaced by a thicker roofed wall (Tsuiji).
In the areas covered in the present report, there were found the remains of a large number of wells- Most of these date from the Heian or Kamakura periods, but one well (SE1230), in the south-west corner of the palace precinct, is from the Nara period and is also noteworthy for the fact that it made use of painted wooden shields, placed side by side to serve as planks around its four sides (See Chapter III/2).
The wooden tablets (mokkan) uncovered among the varios remains were discussed in the 1970 publication Heijo-kyu mokkan. However, a selective list of the more important finds is given in the present report. For example, the tablets bearing the notation Kasofu 過所符, uncovered from the lower strata of site SD1900, were a kind of passport for passing through checkpoints, and thus are an important source material for research concerning the transportation routes of the time. Among the mokkan uncovered from pit SK1979 in the area between the two above-mentioned gates on the west side (Survey No. 18), there are a large number which bear notations having to do with metal nails 釘. The fact that these mokkan were uncovered together with wooden handles for metal utensils, furnace fittings for the insertion bellows and slag left over from molten metal suggests that there was a metal-casting workshop in the vicinity (See Chapter IV/1).
In proportion to the extent of the areas surveyed and also in view of the fact that the surveys in question centered around gates and the surrounding wall, it may be said that the quantity of roof tiles uncoverd was surprisingly small. Among the 261 roof-end round tiles (“noki marugawara”) and 239 roof-end curved tiles (“noki hiragawara”) uncovered, 138 of the former and 102 of the latter･･･48% of the total-were of types used in the Fuji-wara palace. In the case of the area of the Suzaku-mon, 65% of the noki marugawara and 68% of the noki hiragawara were Fujiwara palace types. (See Chapter IV/2).
Pottery treated in the present report is limited to those objects unearthed from site SD1900, i.e., the drainage ditch along the west side of the Shimotsumichi. Taken together, the 183 pieces of hajiki (red pottery) and 139 pieces of sueki (grey pottery) form excellent material for purposes of establishing a chronology of pottery types.
Among those examples of pottery which bear inked Chinese characters, there is a shallow bowl (Tsuki) which bears an inscription reading 秋万呂十口 and which may refer to a set of ten such bowls (found together) that were the property of one “Akimaro”. Others bear inscriptions like 五十戸家 and 五十家 which seem too refer to households in villages governed by the system of one “village” (sato) unit designated for each 50 households, as prescribed in the Taiho legal code of 701. In addition to utensils, also unearthed was the lid of a pottery coffin from Tumulus (Kofun) Period. It has the shape of a hipped (shichushiki) roof (See Chapter IV/3).
Among wooden objects uncovered from site SD1900 were such food receptables as tapered bowls and round boxes (magemono), spindles, bridges to hold Koto strings, combs, wooden clogs (geta), tool handles, etc. From pit SK1983 (Survey No. 18) were recovered such wooden objects as round boxes, spoons, various models in the shape of arrows, knives, etc. (probably used to instruct metal manufactures as to the desired dimensions of orders placed), and handles to such implements as knives, drills and scythes. The 16 painted wooden shields used as side planking in well SE1230 (Survey No.14) fit the description that is given in the “Hayato no tsukasa” article of the Engishiki code (completed 927) with regard to shields employed on ceremomial occasions by the group of people known as Hayato (who lived in Southern prefecture of Kyushu). The lengths of the shields uncovered vary from 149.6 to 152.2cm, and their widths vary from 48.0 to 50.8cm, the average figures being 151.1cm and 48.6cm., respectively. This corresponds almost exactly to the dimensions given in the Engishiki, namely, a length of 5 shaku (151.5cm) and a width of 1.8 shaku (50.5cm). The shields bear sawtooth designs at both their upper and lower ends; swirling designs painted red, white and black are drawn on the center portions, and at the very top are several small holes thought to have been for the purpose of attaching horse hair. These particulars also fit the Engishiki description. On the reverse sides of several of the shields are found such characters as [山], [山地], [海], [海□] and [鳥], written in ink or with a stylus. The patterns by which paint was applied to the obverse side may be classified into two types (See Chapter IV/4).
Chapter V gives attempts at interpretations based on the facts listed above. These deal primarily with the gates and secondarily with the surrounding wall, thoroughfares within the palace precinct, and units of measure used in palace construction.
Supposing that the size of the foundation platform of the Suzaku-mon was approximately the same as that of the area of the horikomi-jigyo carried out at the site, we may hypothesize that the platform extended on all four sides approximately 10 shaku (about 3 meters) beyond the area demarcated by the pillars supporting the roof, and that the platform was on all four sides overhung by eaves. From these facts, it could be supposed that the roof was either of a hipped (yosemune-zukuri) or a hipped and gabled (irimoya-zukuri) construction. However, given the fact that the area of horikomi jigyo was deep (approximately 1.5 meters) and painetakingly filled in to make the ground under the platform as hard as possible, and in light of the extant picture scroll (emakimono) representations of the Suzaku-mon of the Heian-kyu (likewise the principal “front gate” of the palace), we are probably justified to suppose that the Suzaku-mon of the Heijo-kyu had a heavy hipped and gabled roof construction rising several storeys high. The fact that the area of horikomi jigyo of the other two gates is shallower, the fact that their lateral dimensions are somewhat smaller, and especially the fact that the ratio of their shorter to their longer sides is smaller (each of the 5 span between the six pillars on the longer sides to equal thought are 5.05 meters, but each of the 2 span on the shorter sides are thought to equal only 4.5 meters) permit us to suppose that the roofs of those gates were of a simple gable-type construction. The east-west wall (SA1812) built across the northern edge of the Suzaku-mon platform may be seen as giving a clue to the time when the gate was dismantled. By excavation at the sites of this wall’s former foundation stones, it became clear that the wall was built following the end of the gate's use. The fact that it was built only within an area corresponding to the length of the gate’s platform indicates that there was at one time thought to de a need to seal up the opening in question. In this regard, it is highly probable that at the time this wall was built, the surrounding wall on the southern side was still in existence. No traces of such a wall built within the gate area were found at the two other gate sites surveyed. It is probably correct to see the year 791 (Enryaku 10) ･･･ i. e., the year when the various gates of the Heijo palace were physically removed to be newly set up at the Nagaoka palace ･･･as marking the time when the Heijo palace outer gates were dismantled.
The units of measure used in the Heijo-kyu construction were discussed in The Nara Imperial Palace Site Excavation Report II.
However, the present report contains some further material, including the discovery, through surveys of the gates and surrounding walls, that the shaku used in the earliest stages of the palace construction was equal to 0.295 meters (See Chapter V/1).
The fact that many of the roof tiles were diverted to the Heijo palace from the Fujiwara palace after the latter was abandoned is attested by manufacturing techniques, physical composition, special characteristics in ornamental patterns, size and weight, etc. The fact that the tiles newly manufactured at the time of the Heijo palace construction showed in comparison to the Fujiwara-kyu tiles, a tendency to become smaller, is thought to be related to the necessity of producing tiles in large quantities The transition in the composition of the various tile patterns from the Fujiwara palace types to Heijo palace types is treated from the point of view of typology (See Chapter V/2A).
Nextly, consideration is given to the red pottery (hajiki) unearthed from site SD1900. The pieces unearthed from this drainage ditch are divided into 2 groups. Those in the first group show features common to other hajiki unearthed in the Asuka and Fujiwara regions after the latter half of the 7th century, and it is highly probable that the pottery in question was in common use in agricultural villages of the Yamato basin. Those hajiki in the second group are similar to pieces unearthed from various sites around Lake Biwa in Shiga-ken and in the southern part of Kyoto-fu. Those hajiki in the first group are mainly for use in serving food, while those in the second group are mainly for use in cooking. The uses to which the pottery in the two groups was put may thus be seen as mutually complementary. Given the characteristics of excavated site SD1900, the pottery in question was thrown away during the early stages of the palace construction. The same site SD-1900 produced mokkan on which is inscribed the name of a village Ono sato 大野里, which is believed to have disappeared at the time the Heijo palace was built. Further evidence to support the possibility that there existed an agricultural settlement (or settlements) on the same spot before the construction of the Heijo palace may be had in the fact that among the pottery uncovered at SD1900 are pieces with inked characters such as (五十戸家) and (五十家). indicating the existence of rika (“village houses,” corresponding to the terminal elements in the structure of local administration prescribed in the ritsuryo codes). Given the fact that the pottery from site SD1900 was discarded immediately prior to the time when the Suzaku-mon was completed, as well as the fact that no earlier pottery is included and the fact that three is a mixture of pottery from different places of manufacture, it was pointed out that it is possible that the pottery in question was used by ekimin (persons carrying out obligatory labor services) from the various provinces (kuni) who had come to work at building the palace. (See Chapter V/2B).
In addition to the above attempts at interpretation, some further considerations are attempted, based on written historical materials, in regard to such matters as supervision of the gates, entry and exit function of the surrounding wall, and punishments administered to persons who climbed over the wall unlawfully (See Chapter V/3).
Chapter VI deals with the models of the Suzaku-mon and the excavated west-facing gates, construction of which is continuing on the basis of excavation survey results. Each of the models in question is built to 1/10 scale. The work of making a reconstruction of the Suzaku- mon also makes use of comparative data from other excavations, and can usefully refer to the examples to be had in buildings which still remain from the Nara period, as well as to the examples to be had in pictorial scrolls which depict the Heian palace in Kyoto. In the present report, the particulars of the Suzaku-mon reconstructed model are described in the following order: a) general form b) pillars c) entablature (tokyo) d) eaves e) roof f) miscellaneous fixtures g) base plat form h) the roofed adjoining wall. The two west-facing gates in question are thought to have been of identical scale and construction.
They are thought to have had many points in common with the still extant Tegaimon 転害門 at Todaiji.
昭和53年3月31日 発行
奈良国立文化財研究所学報 第34冊
平城宮発掘調査報告IX
－宮城門・大垣の調査－
