A Short Tunnel Behind Rock Sheds
The Watarase Keikoku Railway Nagoshi Tunnel (わたらせ渓谷鐵道名越トンネル) is a single-track brick and stone tunnel built in 1912 at Sori, Azuma-cho, Midori City, Gunma Prefecture, and was registered as a Registered Tangible Cultural Property (structure) on November 2, 2009 (Agency for Cultural Affairs).
The Agency for Cultural Affairs records brick and stone, 32 metres long, registration number 10-0279.
The Ashio Copper Railway
According to Watarase Keikoku Railway, the Ashio copper mine, bought by Furukawa Ichibei in 1877, grew to produce half of Japan's copper, more than horses and a horse tramway could carry, so a railway was built from Kiryu to Ashio. The Ashio Railway opened to Omama in 1911, reached Ashio in December 1912 and was completed to Ashio Honzan in 1914. Nationalised in 1918 as the Ashio Line, it has been run by Watarase Keikoku Railway since 1989.
The Watarase Keikoku Railway Nagoshi Tunnel lies about 1,400 metres south of the Yoshinosawa Flume (Agency for Cultural Affairs).
Value as a Registered Cultural Property
The Watarase Keikoku Railway Nagoshi Tunnel was registered as a structure contributing to the historic landscape of the country. The Agency for Cultural Affairs records a horseshoe section closer to a circle than the government railway standard of the day.
What to Look For
The Agency for Cultural Affairs describes a gently curving 32-metre single-track tunnel with stone side walls and a brick arch; the portals, arch included, are entirely of stone.
Watarase Keikoku Railway's pamphlet notes that both portals of the Watarase Keikoku Railway Nagoshi Tunnel are hard to see behind rock sheds protecting the line; part of the shed at the Sori end stands on old rails.
Visiting
The Watarase Keikoku Railway Nagoshi Tunnel comes into view about two minutes after Sori Station on a Mato-bound train, or about six and a half minutes after Haramuko Station on a Kiryu-bound train (Watarase Keikoku Railway). Watarase Keikoku Railway notes that all of its registered structures can be seen from the train.
Do not enter the tracks; view it from the train, the station or nearby roads. It is located at Sori, Azuma-cho, Midori City, Gunma Prefecture. Of the line's 38 registered structures, the 26 in Gunma and 11 in Tochigi are gathered on the group pages Watarase Keikoku Railway (Gunma Section) and Watarase Keikoku Railway (Tochigi Section).
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Q&A
- When was it built?
- In 1912 (Agency for Cultural Affairs).
- How is it built?
- Brick and stone, 32 metres long (Agency for Cultural Affairs).
- Why are the portals hard to see?
- They are behind rock sheds that protect the line (Watarase Keikoku Railway).
- Where can it be seen?
- The Watarase Keikoku Railway Nagoshi Tunnel comes into view about two minutes after Sori Station on a Mato-bound train, or about six and a half minutes after Haramuko Station on a Kiryu-bound train (Watarase Keikoku Railway).
- When was the Watarase Keikoku Railway Nagoshi Tunnel registered?
- On November 2, 2009.
Basic Information
| Name | Watarase Keikoku Railway Nagoshi Tunnel (わたらせ渓谷鐵道名越トンネル) |
|---|---|
| Location | Sori, Azuma-cho, Midori City, Gunma Prefecture |
| Designation | Registered Tangible Cultural Property (Structure) |
| Year Designated | Registered 2009/11/02 (Heisei 21) |
| Quantity | 1 structure |
| Dimensions | Brick and stone, length 32 metres |
| Owner | Not listed in the national database (line operated by Watarase Keikoku Railway Co., Ltd.) |
| Public Access | Visible from the train |
References
- Watarase Keikoku Railway Nagoshi Tunnel (Database of National Cultural Properties, Agency for Cultural Affairs)
- https://kunishitei.bunka.go.jp/heritage/detail/101/00007852
- Registered Tangible Cultural Properties (Watarase Keikoku Railway, in Japanese)
- https://www.watetsu.com/sightseeing/culture.php
- Pamphlet: Railway Heritage from the Train Window, map notes (Watarase Keikoku Railway, in Japanese)
- https://www.watetsu.com/assets/pdf/sightseeing/culture_yukei_des05.pdf
- History (Watarase Keikoku Railway, in Japanese)
- https://www.watetsu.com/company/history.php
Last verified: 2026.10.12
