Excavated Kawarayato Kiln Site

Kawaratani Pottery Kiln Ruins and Excavated Artifacts (Designated Historic Site by Tokyo Metropolis / Designated Tangible Cultural Property by Tokyo Metropolis)

There is the Kawatani Kiln Ruins along Kawasaki Kaido on the west side of the City Hospital in Omaru, Inagi City. This site is known as a kiln site that fired roof tiles for Musashi Kokubunji during the Nara period. The first excavation survey was conducted in 1956, organized by Inagi Village. In this survey, two kiln sites were discovered, and it was found that these kilns produced roof tiles from the founding period of Musashi Kokubunji and square tiles related to Musashi Kokufu.
In 1998, a second excavation survey was conducted in conjunction with the widening work of Kawasaki Kaido. This survey covered the western part of the area investigated in 1956. A preliminary survey was carried out in 1997, and the main survey began on March 3, 1998. For convenience, points A, B, and C were set from the east side, and excavations were carried out sequentially. As a result, one kiln site and one ash layer were confirmed at point A, one kiln site at point B, and one ash layer at point C (an ash layer is a place where ash accumulated in the kiln was scraped out, with ash and discarded roof tiles piled up in front of the kiln’s firebox). Excavated artifacts include round roof tiles (male tiles), flat roof tiles (female tiles), eave round tiles (abumi tiles), eave flat tiles (u tiles), decorative tiles, square tiles, rectangular tiles, Sue ware, and others. The excavation survey yielded many results and was completed on August 17, 1998.

Excavated Remains of Two Roof Tile Kilns

Kiln No. A, discovered at the eastern end of Point A, was mostly destroyed by a concrete retaining wall, with only a small part of the firebox and the front yard remaining. Although the overall shape is unknown, it is highly likely to be an underground climbing kiln. Ash fields spread out on the southwest side of the kiln remains.
Kiln B is an underground multi-level climbing kiln excavated from the Inagi sand layer at location B. It was discovered in an almost complete form, with the kiln body measuring approximately 6.5 meters in total length and about 1.8 meters at its widest point. The height from the firebox to the top of the flue is approximately 5.5 meters. Inside the kiln's firing chamber, seven levels were constructed for firing roof tiles, and some of these levels were reinforced with "sen" to make it easier to place the products.

Line engraving of a horse drawn inside the kiln site

A horse line drawing was discovered on the right wall of the combustion chamber inside Kiln B, attracting attention. Three horses were depicted in a range of approximately 1 meter by 0.6 meters on the side wall, carved with a stick-like object. The two horses depicted at the bottom were expressed with vigorous lines, showing saddles, hooves, and manes, while the one horse depicted at the top was represented with simple lines, in contrast to the two below. It is believed that the horse line drawings may have been used in rituals related to the kiln. The custom of praying to the fire god when making a kiln and starting a fire is still practiced today. The discovery of horse line drawings inside the kiln is the first of its kind in Japan.

Square tiles engraved with inscriptions

The document is a petition from the village chief to the county, inscribed on a square tile (a brick-like ceramic used for flooring, approximately 28 centimeters in both length and width, and about 8 centimeters thick). The text reads "Kamata Village Chief's Petition, Musashi Province, Ebara County" in 13 characters, which is deciphered as "kamata go no osatsutsushimite geshimosu musashi no kuni ebaragun." This petition was sent from the village chief of Kamata (around present-day Ota Ward) to the office of Ebara County, which governed parts of Shinagawa and Ota Ward. At that time, it is a valuable document indicating that a basic labor system of one county and one village per country was established during the construction of the Kokubunji. Additionally, a "practice writing tile" believed to have been used for practicing the characters before writing the document was also discovered at the same time.

Relationship with Musashi Kokubunji and Musashi Koku

The Kawadaniyato kiln site and Musashi Kokubunji and Musashi Kokufu are located at a close distance of approximately 3.5 to 4 kilometers in a straight line across the Tamagawa River. This investigation revealed that the tiles and bricks fired at the Kawadaniyato kiln site were used during the founding period of Musashi Kokubunji and for Musashi Kokufu. In particular, the square bricks were identified as being for Musashi Kokufu, while the rectangular bricks were for Musashi Kokubunji.

References.
"Report on the Excavation Survey of the Kawatani Kiln Site"
'Inagi City Cultural Property Research Bulletin No. 2, No. 3, No. 4'