Yamakoshi — The Birthplace Terraces
The mountain hamlets of Nijumurago, where coloured carp first appeared among food carp in terraced ponds.
| Area | Yamakoshi, Nagaoka City, Niigata — the former Nijumurago villages |
|---|---|
| Landscape | Terraced rice fields (tanada) and terraced ponds (tanada-ike) stepped into steep hillsides |
| Known for | Birthplace of nishikigoi; post-2004 earthquake recovery landscape |
Yamakoshi is where the guide's history page happened. Farming households kept carp in the pond systems of the terraces, coloured mutations were noticed and kept, and a mountain food practice became an ornamental culture.
The 2004 Chuetsu earthquake devastated Yamakoshi, and its ponds, terraces and koi were part of both the loss and the recovery story told locally — nishikigoi from Yamakoshi became symbols of the district's return. Visiting today is a landscape visit as much as a fish visit: terraces, ponds and scattered hamlets, best taken slowly and in season.
Practical note: Yamakoshi is a lived-in farming district, not an open-air museum. Stay on public roads and viewpoints, and treat working ponds as workplaces.
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.