Deep Bowl-Shaped Vessels from the Sasayama Site: The First Jomon Pottery National Treasure
The Deep Bowl-Shaped Vessels from the Sasayama Site (新潟県笹山遺跡出土深鉢形土器) are 57 Middle Jomon pottery vessels excavated at the Sasayama Site in Tokamachi City, Niigata Prefecture, and in 1999 they became the first Jomon pottery to be designated a National Treasure.
The centrepiece is the flame-style pot (kaengata doki), whose rim bursts upward in projections that look like licking flames. Besides the 57 vessels, a further 871 items from the same period are designated as attached items: 72 pieces of pottery and clay objects, 791 stone tools and stone objects, and 8 lumps of red iron-oxide pigment (bengara). The whole group totals 928 items.
The Deep Bowl-Shaped Vessels from the Sasayama Site were designated an Important Cultural Property on 22 June 1992 and raised to National Treasure on 7 June 1999. According to Tokamachi City Museum, they were also the first National Treasure of any kind in Niigata Prefecture. The museum holds them and shows them in its permanent galleries.
Why They Were Designated
The Sasayama Site lies in the Nakajo district of Tokamachi. Seven seasons of excavation between 1980 and 1985, carried out ahead of the construction of a municipal baseball ground and athletics stadium, uncovered a village that flourished in the Middle Jomon period, roughly 5,500 to 4,500 years ago.
The Agency for Cultural Affairs describes the designation as a group of deep bowls centred on 20 flame-style vessels that were found together. A single flame-style pot is already an icon of Jomon art. What sets Sasayama apart is a large body of such vessels from one settlement, which lets researchers follow the style's range and development as a set.
Some of the 57 vessels show shapes and decoration borrowed from pottery of the Tohoku, Hokuriku, central highland and Kanto regions. The museum treats them as evidence both for how the flame style came into being and for the contacts the people of Sasayama kept with other areas.
Vessel No. 1 has long been singled out as the finest of all Jomon pots for its balance and completeness. It travelled to the Arthur M. Sackler Gallery in Washington in 1992, the Maison de la culture du Japon in Paris in 1998, and the British Museum in London in 2001, introducing Japanese prehistoric art to audiences abroad.
What to Look For
Tokamachi City Museum explains that the flame style arose in the middle Shinano River basin around 3300 BCE and had disappeared by about 2800 BCE. Its hallmarks are cockscomb-like projections rising from the rim and dense, deeply modelled decoration covering the whole surface, all held within a well-proportioned form.
In front of the case, compare the large rim projections from the front and from the side. Then follow the raised ridges that wind between them down into the spirals on the body: the decoration was planned as one continuous scheme from rim to base.
Flame-style pots are often said to have been used in rituals, but the museum notes that no direct evidence of that use has yet been found. What is certain is that they were used for cooking, since some carry scorched residue on the inside. Knowing that these extravagant vessels were set over a fire changes how the interiors look.
Among the 57 are also so-called crown-style pots, another style peculiar to the Shinano River basin, with rim projections shaped differently from the flame style. Seen next to the flame-style vessels, they show how much variety existed within a single regional tradition.
Visiting Tokamachi City Museum
The Deep Bowl-Shaped Vessels from the Sasayama Site are shown in the museum's permanent gallery on the Jomon period and the land of flame-style pottery, at 1-448-9 Nishihonmachi, Tokamachi. The museum is about 10 minutes on foot from the west exit of Tokamachi Station, served by the JR Iiyama Line and the Hokuhoku Line. Parking is free.
Opening hours are 9:00 a.m. to 5:00 p.m., with last entry at 4:30 p.m. The museum closes on Mondays (or the next weekday if Monday is a public holiday) and from December 28 to January 3; from December to February it also closes on Tuesdays. Admission is 600 yen for adults and free for junior high school students and younger.
In the National Treasure room, the central case alternates between vessel No. 1 and vessel No. 6. If you want to see a particular piece, check the display schedule on the museum's website before you go.
Tripods and flash are not permitted in the galleries, and commercial photography is prohibited. Rules can change with the exhibition, so follow the signs on site.
Q&A
- Where can I see the Deep Bowl-Shaped Vessels from the Sasayama Site?
- At Tokamachi City Museum, 1-448-9 Nishihonmachi, Tokamachi, about 10 minutes on foot from the west exit of Tokamachi Station.
- When were the Sasayama flame-style pots designated a National Treasure?
- On 7 June 1999. They were the first Jomon pottery to become a National Treasure, having been designated an Important Cultural Property in 1992.
- How many items make up the Deep Bowl-Shaped Vessels from the Sasayama Site?
- The designation covers 57 deep bowls, plus 871 attached items: pottery and clay objects, stone tools and objects, and lumps of red pigment.
- What are the opening hours and admission fee of Tokamachi City Museum?
- 9:00 a.m. to 5:00 p.m. (last entry 4:30 p.m.), closed Mondays, and also Tuesdays from December to February. Adults pay 600 yen; junior high school students and younger enter free.
- Is the famous flame-style pot No. 1 always on display?
- The central case in the National Treasure room alternates between No. 1 and No. 6. Check the schedule on the museum's website.
Basic Information
| Name | Deep Bowl-Shaped Vessels from the Sasayama Site (Niigata Prefecture) |
|---|---|
| Location | Tokamachi City Museum, 1-448-9 Nishihonmachi, Tokamachi City, Niigata Prefecture |
| Designation | National Treasure (Archaeological Materials) |
| Year Designated | Designated National Treasure 1999/06/07 (Heisei 11); Important Cultural Property 1992/06/22 (Heisei 4) |
| Quantity | 57 deep bowls (871 attached items) |
| Dimensions | Varies by vessel (no collective figure in the Agency for Cultural Affairs database) |
| Owner | Not listed in the Agency for Cultural Affairs database (held by Tokamachi City Museum) |
| Public Access | On permanent display at Tokamachi City Museum. 9:00 a.m. to 5:00 p.m., adults 600 yen |
References
- Agency for Cultural Affairs, Database of National Cultural Properties: Deep Bowl-Shaped Vessels from the Sasayama Site
- https://kunishitei.bunka.go.jp/bsys/maindetails/201/10315
- Cultural Heritage Online: Deep Bowl-Shaped Vessels from the Sasayama Site
- https://online.bunka.go.jp/heritages/detail/187852
- Tokamachi City Museum: Deep Bowl-Shaped Vessels from the Sasayama Site
- https://www.tokamachi-museum.jp/archives/bunka001/
- Tokamachi City Museum: The Jomon Period and the Land of Flame-Style Pottery
- https://www.tokamachi-museum.jp/p-exhibition/p-ex01/
- Tokamachi City Museum: Visitor Information
- https://www.tokamachi-museum.jp/guide/
Last verified: 2026.09.27