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 a kiln site along the Kawasaki Highway on the west side of the Inagi City Hospital in Omaru. This site is known as the kiln site that produced tiles for the Musashi Kokubunji during the Nara period. The first excavation was conducted in 1956, organized by Inagi Village. During this survey, two kiln sites were discovered, and it was found that tiles from the period of the establishment of Musashi Kokubunji and square tiles related to Musashi Province were produced at these kilns.
In 1998, a second excavation was conducted due to the widening of the Kawasaki Highway. This survey focused on the western part of the area investigated in 1956. A preliminary survey was conducted in 1997, and the main investigation began on March 3, 1998. For convenience, points A, B, and C were set from the east, and excavations were carried out sequentially. As a result, one kiln site and one ash site were confirmed at point A, one kiln site at point B, and one ash site at point C (an ash site is where ash accumulated in the kiln was removed, with ash and discarded tiles piled in front of the kiln's mouth). The excavated artifacts include round tiles (male tiles), flat tiles (female tiles), eaves round tiles (abune tiles), eaves flat tiles (u tiles), noshi tiles, square tiles, rectangular tiles, and Sue ware. The excavation left many achievements and was completed on August 17, 1998.

Excavated Remains of Two Roof Tile Kilns

The 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 firing mouth and the front yard remaining. The overall shape is unclear, but it is highly likely to be an underground climbing kiln. To the southwest of the kiln site, an ash field was spread out.
Kiln No. B is an underground climbing kiln with multiple levels, created by excavating the Inagi sand layer within point B. It was discovered in almost complete form, with the kiln body measuring approximately 6.5 meters in total length and about 1.8 meters in maximum width, and a height of about 5.5 meters from the firing mouth to the top of the flue. The firing chamber of the kiln has seven tiers built for firing tiles, and some of the tiers were reinforced with 'sen' to facilitate the placement of 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.

Reference citations.
"Report on the Excavation of the Kawagatani Pottery Site"
"Inagi City Cultural Heritage Research Bulletin No. 2, 3, and 4"