Niigata Beyond Ojiya
Uonuma and the wider Chuetsu hills — the rest of the home prefecture's koi geography.
| Scope | Uonuma City and neighbouring Chuetsu districts within the historic Nijumurago range |
|---|---|
| Prefectural status | Nishikigoi designated Niigata's official ornamental fish, 5 May 2017 |
| Character | Scattered mountain production alongside the Ojiya–Yamakoshi core |
The historic Nijumurago spanned what are now Nagaoka (Yamakoshi), Ojiya and Uonuma, and koi keeping never respected modern city borders. Uonuma and the surrounding valleys share the terraced-pond landscape and the same origin story.
For visitors, the practical shape is a core and a penumbra: Ojiya and Yamakoshi hold the public facility and the most concentrated sights, while the wider prefecture rewards drivers with pond-dotted valleys rather than single attractions. This page stays at overview level because public, checkable facility facts thin out beyond the core — a deliberate choice over padding the guide with unverified listings.
Sources: Wikipedia (CC BY-SA — summary in our own words, credit only); All Japan Nishikigoi Promotion Association official; Ministry of Agriculture, Forestry and Fisheries (MAFF) and Finance Ministry trade statistics as published; Japanese Agricultural Standard (JAS) for nishikigoi variety names and definitions (2022); Niigata Prefecture, Ojiya City, Nagaoka City (Yamakoshi) and Nishikigoi no Sato official; Japan National Tourism Organization (JNTO) visitor statistics; USDA APHIS and Australian DAFF official import guidance. Checked 6 November 2026.