Hatten Ruins

Hatten Site: Clay Masks and a Circular Hall on the Kitakami River

Five noses, two mouths, one ear. Eight clay fragments, modeled to represent parts of a human face, were lifted from two earthen pits during a 1976 excavation in northern Honshu. They had sat there for roughly 3,500 years, in a Late Jomon grave field on a low plateau above the Kitakami River. Archaeologists believe the fragments once belonged to ritual masks. They are the first such pieces in Japan to have been recovered from a clearly documented excavated context.

The place where they came to light is now the Hatten Site (八天遺跡), in the Saraki district of Kitakami City, Iwate Prefecture. Designated a national Historic Site in 1978, it covers roughly two hectares on a tongue-shaped plateau formed by a bend of the river, on the eastern margin of the Kitakami Basin. The clay face fragments themselves were designated an Important Cultural Property in June 1992.

A Site Found Beneath Rice Paddies

The plateau looked unremarkable for most of recorded history: gently rolling farmland on a quiet edge of village life. In the mid-1970s, when the area was being developed for paddy rice cultivation, traces of an underlying settlement began to surface. Five seasons of excavation between 1975 and 1977, led by Kitakami's cultural authorities, revealed that almost the entire plateau was perforated with the post-holes of dwellings and the dark circles of storage and burial pits.

Most of what was recorded dates to the Late Jomon period, roughly 4,400 to 3,200 years before present. But Hatten is not a single-period site. A thin Paleolithic layer was identified in the southeastern corner. Above the Jomon strata, in the central plateau, came four Heian-period pit dwellings, then medieval ditches and a well. The Kitakami Board of Education returned to the site for further survey work in 2020 and 2021, reporting a compound hearth datable to the very end of the Middle Jomon, around 4,500 years ago. The settlement was already taking shape earlier than the original excavations had suggested.

The Circular Hall That Kept Shrinking

What sets Hatten apart, even among well-studied Jomon settlements, is a single building near the center of the plateau. It was perfectly circular in plan, with one ring of post-holes inside another, and another within that. By careful tracing, excavators concluded that the structure had been rebuilt close to ten times on the same spot. Each successive version was slightly smaller than the one before. The largest reached about seventeen meters across; the latest measured roughly eight.

A Jomon dwelling of even ten meters in diameter is unusual. One of seventeen, persistently rebuilt on the same axis across generations, is in another category altogether. Specialists consider it almost certainly a communal structure: a gathering hall, a ritual building, or something between the two. Villages with such a building are rare in Japan, and its presence is read as a sign that Hatten served as a regional center rather than as a single household cluster.

Why the hall shrank with each rebuild is not yet settled. One reading is that the rituals it served grew more intimate, or more exclusive, over time. Another is purely practical: each rebuilding may have been keyed to the surviving timber of the previous structure. Excavators have so far resisted choosing between the explanations.

Eight Clay Fragments, One Quiet Puzzle

The clay face parts came from elsewhere on the plateau: from two of the large, deep pits that punctuate the settlement layer, dug in a distinctive flask-shape or beaker-shape and reaching well below the surrounding ground surface. Two of these pits each held several of the fragments. The totals, much commented on locally because of the name of the site itself (八天 means literally "eight heavens"), come to exactly eight: five noses, two mouths, and one ear.

None has yet been found attached to a complete mask. The pieces are small, hollow at the back, modeled with care around the nostrils and lips. They imply a larger object once made of clay, wood, or perhaps hide. Interpretations of how they were used vary. Some specialists read the pits as graves and the fragments as parts of masks placed on or near the dead; others see the pits as discarded storage features and the fragments as components of doll-like figures broken at the conclusion of a seasonal rite. Each fragment is small enough to hold in one hand, but the questions they raise reach deep into Jomon ritual life. The eight pieces are now held by the city of Kitakami.

Why the Site Was Designated

Hatten was added to the national register of Historic Sites on 22 February 1978, under the category covering shell middens, settlement remains and tombs. The reasoning of the Agency for Cultural Affairs drew together the threads above: the unusually large communal building, the clay mask fragments recovered in a clear excavated context, and the evidence that the plateau served as a central settlement within its region. Subsequent campaigns have added a fourth thread: a continuity of occupation across the Middle and Late Jomon periods that few sites in northern Tohoku can match.

Visiting the Site and Where to See the Finds

The site itself is currently a quiet stretch of fields. Kitakami's Cultural Property Division is preparing a long-term plan for the preservation and interpretation of the plateau, but at present the visible remains have not been laid out as a park, and the location is not promoted for casual tourism. Travelers with a specific interest in Jomon archaeology can approach the area by car, roughly seventeen minutes from JR Murasakino Station on the Tohoku Main Line, but should treat the visit as a landscape pilgrimage rather than an on-site museum experience.

The artifacts, including the eight clay face fragments, are held by Kitakami City. A selection of Jomon material from the area can be seen at the Kabayama Historical Park Jomon Hall (Kabayama Rekishi no Hiroba Jomonkan), a small but well-curated museum some eight kilometers south of Hatten. The hall serves the adjacent Kabayama Site, another national Historic Site with a reconstructed Jomon village and stone settings. Admission is free; the museum closes in winter, so seasonal hours are worth confirming before traveling.

The wider area rewards a slow day. Tenshochi Park, about ten kilometers south along the Kitakami River, is one of Tohoku's most famous cherry-blossom corridors in late April. The Kunimi-san temple ruins, a prefectural Historic Site west of the city, preserve traces of a major medieval Buddhist complex in the hills. And for those drawn to living folk traditions, Kitakami's Oni-no-Yakata theater hosts performances of Onikenbai, the local "demon sword dance" recognized as an Important Intangible Folk Cultural Property of Japan.