Jomo Electric Railway Kasukawa Bridge

Jomo Electric Railway Kasukawa Bridge: A Living Heritage of Early Showa Railway Engineering

Standing quietly over the gentle waters of the Kasukawa River in eastern Maebashi City, Gunma Prefecture, the Jomo Electric Railway Kasukawa Bridge is a steel railway bridge that has served local communities since 1928. Registered as a national Tangible Cultural Property in 2009, this four-span plate girder bridge is a remarkable survivor of Japan's early Showa-era railway expansion, bearing witness to nearly a century of regional transportation history. For international visitors seeking authentic encounters with Japan's industrial heritage beyond the well-trodden tourist paths, this bridge offers a quietly compelling destination along one of Gunma Prefecture's most charming local railway lines.

History and Origins of the Kasukawa Bridge

The Kasukawa Bridge was built in 1928 (Showa 3) as part of the original construction of the Jomo Electric Railway's Jomo Line, which opened on November 10 of that year, connecting Chuo-Maebashi Station to Nishi-Kiryu Station across a 25.4-kilometer route along the southern foothills of Mount Akagi. The railway was conceived by local entrepreneurs and industrialists who envisioned an electric rail network to serve the textile-producing communities of Gunma Prefecture, and the entire line was constructed at a remarkably swift pace, with work beginning in February 1928 and the line opening just nine months later.

The Kasukawa Bridge spans the Kasukawa River, a waterway that flows north to south through the eastern part of Maebashi City. At 42.1 meters in length and 2.1 meters in width, the bridge is a single-track, deck-type structure composed of four steel plate girder spans, each using 30-foot plate girders. The bridge originally rested on hexagonal-shaped piers, a design characteristic of railway bridges from this period.

Typhoon Kathleen and the Bridge's Transformation

In September 1947, Typhoon Kathleen struck the Kanto region with devastating force. Though the typhoon itself did not make landfall, its interaction with a stationary weather front triggered extraordinary rainfall across the region, causing catastrophic flooding and landslides particularly around the slopes of Mount Akagi. In Gunma Prefecture alone, the disaster claimed 592 lives. Rivers throughout the region overflowed their banks, and critical infrastructure including roads, railways, and bridges sustained severe damage.

The Kasukawa Bridge did not escape unscathed. The flooding damaged the bridge's piers and abutments, necessitating significant repairs. During the reconstruction, the original hexagonal-shaped piers were replaced with cylindrical reinforced concrete piers, and the abutments were reinforced with additional concrete. Remarkably, however, the steel girders themselves suffered only minor damage and were retained in their original form. This means that visitors today can still see the very same steel bridge spans that carried the first trains across the Kasukawa River in 1928.

Why It Was Designated as a Registered Tangible Cultural Property

The Kasukawa Bridge was officially registered as a national Tangible Cultural Property (Registered Tangible Cultural Property for Buildings) on April 28, 2009. The registration recognizes the bridge as a significant example of modern civil engineering heritage that has played a vital role in supporting regional transportation.

Several factors contributed to its designation. The bridge retains its original 1928 steel plate girders, making it a rare surviving example of early Showa-era railway construction technology. The combination of original steel superstructure with post-Typhoon Kathleen reinforced concrete substructure tells a layered story of engineering resilience and adaptation. Furthermore, as part of the Jomo Electric Railway, the bridge represents the broader historical narrative of regional railway development driven by local communities during Japan's modernization period.

It is worth noting that the Jomo Electric Railway has several other structures registered as Tangible Cultural Properties, including the Watarase River Bridge, the Ogo Train Depot, the Nishi-Kiryu Station building, and the Ogo Substation, forming a rich collection of early Showa railway heritage.

Highlights and Points of Interest

The Kasukawa Bridge's appeal lies in the combination of its historical authenticity and the pastoral setting in which it stands. Unlike bridges in busy urban environments, this structure sits amid a landscape of rice paddies and quiet residential areas, with Mount Akagi providing a dramatic backdrop to the north. The sight of a two-car electric train crossing the nearly century-old bridge against this rural scenery captures the essence of Japan's local railway culture.

For railway enthusiasts and photographers, the bridge offers excellent vantage points from the riverbanks on either side. The riveted steel plate girders, the cylindrical concrete piers, and the 95 wooden railway sleepers that line the bridge deck are all clearly visible from below. The best times for photography are early morning and late afternoon, when the low-angle sunlight highlights the bridge's structural details against the sky.

The experience of riding across the bridge aboard the Jomo Line train itself is equally rewarding. With trains running every 30 minutes during daytime hours, visitors can easily time their journey to include a crossing. The Jomo Electric Railway also operates a bicycle-friendly service (Cycle Train), allowing passengers to bring their bicycles aboard at no extra charge, making it possible to explore the bridge and surrounding area by bike after arriving by train.

The Jomo Electric Railway: A Heritage Railway Experience

The Jomo Electric Railway (commonly known as Joden) is itself a destination for railway heritage enthusiasts. Founded in 1926 and operational since 1928, this local railway runs between Chuo-Maebashi and Nishi-Kiryu along the southern foot of Mount Akagi. From its inception, the line was built to an ambitious standard for a rural railway, using 1,500-volt direct current electrification.

Several features make the Jomo Line particularly appealing to visitors. The Ogo Train Depot, a wooden truss-structure facility built in 1928 and also registered as a Tangible Cultural Property, houses some of Japan's oldest operational electric railcars, including the DeHa 101, which dates from the railway's opening year and is recognized as a Gunma Prefecture Modern Heritage site. Special event days allow visitors to ride this historic vehicle along the main line. The Nishi-Kiryu Station, with its distinctive Mansard-roofed station building from 1928, has been selected as one of the top 100 stations in the Kanto region.

Since January 2026, the Jomo Electric Railway has introduced IC card compatibility across all stations, accepting both the regional nolbé card and major nationwide transit IC cards including Suica and PASMO, making the line more accessible than ever for international visitors.

Nearby Attractions and Surrounding Area

The area around the Kasukawa Bridge offers several additional points of interest for visitors. The Kasukawa History and Folk Museum, located a short distance from Kasukawa Station, provides insight into the local history and traditional culture of this rural community. The former Kasukawa Village area retains a quiet, unhurried atmosphere that gives visitors a genuine sense of life in the Japanese countryside.

Further along the Jomo Line, the Ogo Station area is home to the aforementioned Ogo Train Depot, which can be visited by prior appointment. The charming Maebashi City Runapaku amusement park, accessible from Chuo-Maebashi Station, is known as one of Japan's most affordable amusement parks, with rides costing as little as 10 yen. For nature lovers, the slopes of Mount Akagi offer hiking trails, hot springs, and panoramic views of the Kanto Plain.

The nearby city of Kiryu, at the eastern end of the Jomo Line, is famous for its textile heritage and traditional townscape, and can be combined with a visit to the Watarase Keikoku Railway for a full day of railway heritage exploration.