Large-scale buildings and graves appear one after another from within a huge pile of earth. The thickly mounded, undisturbed fill was a treasure house of new discoveries.

The site from above

The vicinity of the site in the Jōmon period was a gently rolling tableland, but was rapidly inundated due to subsidence of the land and alluvial flooding. Because the ring-shaped piled-earth feature was covered with flood deposits from the Nara period on, it was not destroyed by later development and thus discovered  undisturbed. Surrounding an intentionally dug central depression, piled earth spread in a donut shape more that 150 m in external diameter, with a width estimated at greater than 20 m. The greatest thickness was 1.8 m.

Adapted from Hakkutsu sareta Nihon rettō 2014 [Excavations in the Japanese Archipelago, 2014] (Bunkachō [Agency for Cultural Affairs], ed., Asahi Shimbun Publications, 2014).
Schematic diagram of the features

Pit burials were on the piled earth's northern part, and buildings on the southern part, with scorched-earth-paved structures concentrating in one portion. While the pit burials were made in a limited span in the Final Jōmon, the scorched-earth-paved structures were built repeatedly in the same locations over a long period.

Adapted from Hakkutsu sareta Nihon rettō 2014 [Excavations in the Japanese Archipelago, 2014] (Bunkachō [Agency for Cultural Affairs], ed., Asahi Shimbun Publications, 2014).

Human skeleton, extended burial

Discovered in the slope of the piled earth's southern part. The burial pit was made by destroying the remains of a scorched-earth-paved structure. A mature female approximately 150 cm tall, the pelvis had trace marks from giving birth. A red-painted spouted vessel was placed next to the head as a grave good. Examples of human skeletons being recovered in complete form at sites atop tablelands but not from shell middens are very rare. Preservation was probably good because the scorched earth laid down in the building neutralized the soil's acidity.

Orderly alignment of pit burials in the piled earth's northern part

Nearly all were dug as well-formed rectangles about 2 m in length. There were small holes at each end on the floor of the pit, and it appears that post-like members had been erected. Their alignments were uniformly either in parallel or at a perpendicular, with many examples of one side overlapping another burial. Were graves newly made using posts from ancestors' burials that jutted up above ground as points of reference? Another highly unusual feature is the placement in many pit burials of small pottery items such as spouted vessels or vases, and by reference to the extended burial from the piled earth's southern part, the position of the pottery permits inferring the orientation of the head. Vessel types and positions vary minutely among small groups, which may provide data suitable for unraveling burial methods and relations among people who lived in the settlement.

Scorched-earth building

At 11.5 m on a side, with an area of about 130 square meters, this is the largest building at the site. White clay was pasted into the hearths, which would turn into deep red scorched earth when a fire was built. The hearth floors were burned to an unusual degree, and it is thought that fires were frequently made and the resulting scorched earth scattered over the building's interior to maintain a red floor. In addition to the four main pillars, supporting pillars lined the edge of the walls, and two auxiliary hearths were found towards the front of the photo, plus an entrance to the back underneath the fill. It was also learned that the structure had been renovated three times.

Adapted from Hakkutsu sareta Nihon rettō 2014 [Excavations in the Japanese Archipelago, 2014] (Bunkachō [Agency for Cultural Affairs], ed., Asahi Shimbun Publications, 2014).

Nagatake Site, Kazo City, Saitama Prefecture

A ring-shaped piled-earth feature

At the Nagatake site, located beside the Tone river which flows at the north end of the Kazo lowland in the northeastern portion of Saitama prefecture, a ring-shaped piled-earth feature from the latter portion of the Late Jōmon to the first portion of the Final Jōmon periods (about 4,500–3,500 years ago) was discovered.

The act of piling up earth within the settlement is widely seen across eastern Japan for the latter half of the Jōmon period, but it is mainly in the eastern side of Kantō that it  was left in the shape of a giant ring. Ring-shaped piled-earth features were first recognized at the Terano Higashi site in the city of Oyama, Tochigi prefecture, in 1993, and there have been subsequent reports one after another, while the nature of these features has been variously debated. With the discovery of buildings and other features from within the piled earth in the Nagatake investigation, it is hoped that understanding of the actual condition of these features will advance.

Discovery of a group of pit burials and buildings paved with scorched earth

The piled earth of the investigation was divided into northern and southern parts by a small depression as border. Of the two, on the inner slope of the northern part, 60 pit burials with pottery of the first portion of the Late Jōmon period as grave goods were discovered. In contrast, a complete skeleton buried with pottery was recovered from the southern part, and based on the positions and types of the grave goods it is thus possible to reconstruct the conditions of interment in the northern group of pit burials.

Additionally, in the center of the southern part of the piled-earth feature, seven buildings with scorched earth spread over the floors were discovered. These were surrounded by buildings lacking layers of scorched earth, and one portion had had the roofs deliberately torched, and special goods placed within, at the time of abandonment, so these buildings are thought to have been special for the people of the settlement.

Homing in on the riddle of the ring-shaped piled earth feature

As seen in the figure, the group of pit burials and buildings had separate distributions, and the ring-shaped feature is seen to be comprised of parts for different purposes.

Also, the pile of earth was not built up all at once, rather, it has become clear that a variety of actions from that time overlapped, such as the leveling of ground in preparation for erecting a building or covering an area during rebuilding, discarding used building materials in bulk, and spreading cover at particular locations. It was possible to obtain these important results precisely because observations could be made over a wide area of the thickly piled earth. (Kurosaka Teiji)

(principal artifacts Nagatake Site)

Painted, footed bowl

First portion of the Final Jōmon period, approximately 3,000 years ago
Rim diameter: 30.5 cm; height: 18.5 cm.
Recovered from a pit burial. The foot is broken, but as the broken surfaces had been arranged together, it is thought to have been used in that fashion from the time prior to becoming a grave good. Neither the composition of the design nor the painting are known from examples near the site, and it exudes a unique style no other vessel can approach.

Spouted vessels

First portion of the Final Jōmon period, approximately 3,000 years ago
(Item at right front) Rim diameter: 7.8 cm; height: 10.8 cm.
All of these were grave goods in pit burials. Spouted vessels are closely connected with ritual. Among these the item at right front has a human face added to a design and shape mimicking those of the Tōhoku region, and thus appears to have been anthropomorphicized. The bottom has wear, suggesting it was not made as a grave good but had already been in use. Perhaps it was treated as a special liquor vessel in which a deity resided.

Animal-shaped clay objects

Latter portion of the Late Jōmon–first portion of the Final Jōmon periods, approximately 3,500–3,000 years ago
(Central dog-shaped item) Length: 7.1; width: 2.6 cm; height: 3.8 cm.
As items in the shapes of, from the left, a turtle, a dog, and a wild boar, the recovery of all three types together is rare. Were prayers of thanks perhaps being offered to these animals deeply connected with people's daily lives? While appearing hastily made, the precision of Jōmon modeling can be seen in the charming workmanship that manages to capture the key points.

Clay figurines and plaques

Latter portion of the Late Jōmon–first portion of the Final Jōmon periods, approximately 3,500–3,000 years ago
(Item at lower left) Length: 11.0 cm; width: 8.3 cm; thickness: 1.8 cm.
All of these are clay objects regarded as ritual paraphernalia. The upper row of figurines (dogū) are examples of mimizuku dogū (named for the resemblance to a horned owl, mimizuku) commonly made in the Kantō region. They have ear ornaments, and are painted red all over. Clay plaques (doban) on the lower row in rare instances are made with human faces or animal-like expressions. The items on the left and right appear to mimic human faces, while the central item is fitted with breasts, a tail, and legs, and in the same manner as for animal-shaped clay objects a hole has been opened as the anus.