The Ōu Mountains: Japan's Longest Range, Spanning Tohoku
Location & Extent
- Length: ~500 km (310 mi) — **Japan's longest mountain range**.
- Orientation: North–South along the **Ou Backbone** (Ōu Sanmyaku).
- Prefectures: Aomori → Iwate → Akita → Yamagata → Miyagi → Fukushima.
- Divides: **Tōhoku Region** (Pacific side) from **Japan Sea side** ( Dewa / Shōnai).
Sub-Ranges & Key Peaks
| Section | Prefectures | Notable Peaks / Features |
|---|
| Northern Ōu | Aomori, Iwate | Hakkōda (1,585 m), Iwate (2,038 m), Akita Koma (1,637 m) |
| Central Ōu | Akita, Yamagata | Chōkai (2,236 m), Gassan (1,984 m), Asahi Range |
| Southern Ōu | Miyagi, Fukushima | Zao (1,841 m), Azuma (1,949 m), Adatara (1,700 m) |
Hydrology: Japan's Water Tower
Source of major rivers:
- Kitakami (Pacific, 249 km) — Iwate/Miyagi.
- Mogami (Japan Sea, 229 km) — Yamagata.
- Abukuma (Pacific, 234 km) — Fukushima/Miyagi.
- Omono (Japan Sea) — Akita.
Geology & Activity
- Volcanic arc (subduction of Pacific Plate).
- Active volcanoes: **Iwate, Akita Koma, Chōkai, Zao, Azuma, Adatara** — monitored by JMA.
- Abundant **onsen** (hot springs) — e.g., Nyuto, Ginzan, Zao, Tsuchiyu.
Recreation & Access
- Hiking: Chōkai, Gassan, Zao, Hakkōda — alpine flora, marshlands.
- Skiing: Zao (frost trees), Appi, Hakkōda, Geto.
- Transport: Yamagata Shinkansen (Fukushima–Shinjō) parallels west; Akita Shinkansen (Morioka–Akita) crosses north. JR Ōu Main Line follows valleys.
Map Reference
On a map: Draw a line from **Aomori City (N)** → **Hakkōda** → **Towada** → **Akita** → **Yamagata** → **Zao** → **Fukushima (S)**. That's the Ōu spine.
Wanderlust World