Oyu Stone Circles
Oyu Kanjo Resseki · Manza and Nonakado Circles
Late Jomon 2000–1500 BCE·Jomon Late·🇯🇵 Akita Prefecture, Kazuno City, Towada–Oyu district, Manza/Naka plain at foot of Towada caldera, Japan
About
About Oyu Stone Circles
Twin Late Jomon double-stone circles (2000–1500 BCE) — Manza (46 m dia) and Nonakado (42 m dia) placed either side of prefectural road at Oyu, Kazuno, each concentric with sundial-like 2.1 m central standing stone aligned to midsummer sunset and Mt. Towada, with surrounding hut floors and cremation pits. UNESCO 2021 component 1632-014, celebrated for precise concentric layout 4000 years pre-orientation and 7000 undressed river cobbles.
Why it mattersMost formalized Jomon stone calendar proving pre-literate astronomical-mountain alignment; exemplifies Jomon ritual complexity without hierarchy.
Open questions
Mysteries & theories
Mysteries
- 01Intentional sunset alignment precision — coincidence vs solstice survey?
Theories
- 01Mountain–sun dual worship model
Theories are interpretations, not findings. The seal above tells you how much scholarly weight the place carries.
History
How it came to be
- Built
- c.2000–1500 BCE Late Jomon
- Period
- Late Jomon 2000–1500 BCE
- Culture
- Jomon Late
- Builders
- Jomon foragers / ritualists
- Purpose
- Sun-mountain cult ceremonial calendar and mortuary plaza
- Abandoned
- c.1500 BCE
- Rediscovered
- 1931 found during road widening; excavated 1932 S. Umehara
- Excavation
- Partially excavated
c.2000 BCE
Manza circle 46 m built with 4000 cobbles
1931
Designated Special Historic Site; Oyu museum erected
On the ground
Structures & features
40.2714° N · 140.8044° E · 245 m · 1 mapped feature
Manza Stone Circle (46m)
stone circleOuter ring with central 2.1 m standing stone
40.2715° N · 140.8048° E
Gallery