Iwai Bridge

Iwai Bridge: The "Spectacles Bridge" of Katsunuma Wine Country

Standing gracefully over the Hikawa River in Katsunuma, Koshu City, Yamanashi Prefecture, Iwai Bridge (祝橋, Iwai-bashi) is a beautifully preserved concrete arch bridge from the early Showa period. Known affectionately as "Megane-bashi" (Spectacles Bridge) for its distinctive arched silhouette, this 1930-built structure is one of only three surviving concrete arch bridges in Yamanashi Prefecture — and the largest among them. Registered as a national Tangible Cultural Property in 1997 and recognized as a Modern Industrial Heritage site, Iwai Bridge stands as an enduring symbol of Katsunuma's transformation into one of Japan's most celebrated wine-producing regions.

A Bridge Born from the Wine Industry

The story of Iwai Bridge is inseparable from the rise of Japanese winemaking. The Katsunuma area, particularly the Iwasaki district of the former Iwai Village, has been cultivating grapes since the Edo period and pioneered commercial wine production in the Meiji era. In 1877, the Dai Nippon Yamanashi Wine Company — Japan's first private wine venture — was established here, sending two young men to France to learn modern viticulture techniques.

When Katsunuma Station (now JR Katsunuma Budokyo Station) opened on the Chuo Line in 1913, it created an urgent need to transport grapes and wine from the vineyards on the west bank of the Hikawa River to the railway station on the eastern hills. A wooden suspension bridge was hastily built in 1914 as the second-generation Iwai Bridge, but it could only accommodate horse-drawn carts and was too fragile for the motorized trucks that were becoming essential for large-scale shipments.

By the late 1920s, the aging suspension bridge could no longer keep pace with the growing wine industry. In 1930, a modern reinforced concrete arch bridge was constructed at a total cost of 40,458 yen — a significant investment for the time. The opening ceremony, held in 1931, drew large crowds from surrounding towns and villages, and the elegant new bridge quickly became a proud landmark of the region.

Why Iwai Bridge Became a Cultural Property

Iwai Bridge was registered as a national Tangible Cultural Property on May 7, 1997, in recognition of several key attributes. As a concrete arch bridge spanning 58.6 meters with a width of 6.6 meters, it was engineered to cross the Hikawa gorge without any mid-stream piers — a remarkable technical achievement for its era. The bridge is the second-oldest of the three remaining concrete arch bridges in Yamanashi Prefecture, and it is the largest in scale among them.

Beyond its engineering significance, Iwai Bridge served as a crucial link in the transportation network that enabled Katsunuma's grape and wine industries to flourish. It is recognized as part of Japan's Modern Industrial Heritage and is also featured in the Japan Heritage story "Landscapes Woven by Vineyards," which celebrates the cultural landscape of Katsunuma's winemaking traditions.

Highlights and Things to See

Today, Iwai Bridge is closed to vehicle traffic — a new bridge (Shin-Iwai Bridge) was built downstream in 1985 to handle modern traffic. However, the original bridge remains fully accessible on foot, and crossing it is a memorable experience.

As you walk across, you will notice a metal-covered water pipeline running along the center of the bridge. Since 2005, Iwai Bridge has been repurposed as an aqueduct, carrying water from Kotokawa Dam to the surrounding communities. Benches and interpretive panels have been installed alongside the pipeline, inviting visitors to pause and take in the scenery.

The views from the bridge are spectacular. Looking east, you can see Mount Kashio, the site of the historic Boshin War battle and the dramatic "Torii-yaki" fire festival. Gazing west, the Hikawa River meanders below as vineyards and wineries stretch toward the vast Kofu Basin beyond. On clear days, the panorama is breathtaking.

The bridge's parabolic arch form is best appreciated from the adjacent Shin-Iwai Bridge or from the riverbanks below, where the "spectacles" silhouette becomes strikingly apparent — especially beautiful when framed by cherry blossoms in spring or autumn foliage in late October.

Three Generations of Iwai Bridge

The current concrete arch bridge is actually the third bridge to bear the Iwai name at this location. The first Iwai Bridge was a wooden cantilever structure located slightly upstream at the present-day Taro Bridge site. It was destroyed in the devastating flood of 1907 — a catastrophe so severe that over 2,000 local farmers were forced to relocate to Hokkaido.

The second Iwai Bridge, a wooden suspension bridge, was built in 1914 following the opening of Katsunuma Station. While it served its purpose for horse carts, its inability to bear the weight of trucks spurred the construction of the current reinforced concrete bridge in 1930.

Each generation of the bridge reflects a chapter in Katsunuma's development — from traditional agriculture, through the arrival of the railway, to the emergence of a modern wine industry.

Exploring the Surrounding Area

Iwai Bridge sits at the heart of one of Japan's richest cultural and gastronomic landscapes. The following attractions are all within easy reach:

• Katsunuma Wineries: Over 30 wineries cluster in the area west of the bridge. Many offer tastings, vineyard tours, and direct sales. Notable names include Kurambon Wine, Château Mercian, and Maruki Winery — the latter founded by Ryuken Tsuchiya, one of the two pioneers sent to France in 1877.
• Daizenji Temple (National Treasure): Known as the "Grape Temple," Daizenji dates back to 718 AD. Its main hall (Yakushido) is a National Treasure and one of the oldest wooden structures in the Kanto region. The temple even produces its own wine, which visitors can enjoy while contemplating the Japanese garden.
• Former Tanaka Bank Building: A charming example of pseudo-Western architecture from the Meiji era, this registered Cultural Property stands on the old Koshu Kaido highway.
• Katsunuma-shi Yakata Ruins: Just north of the bridge, this well-preserved site of a medieval warrior's fortified residence offers a fascinating glimpse into Japan's feudal past. From the ruins, you can look down at the Hikawa gorge and appreciate why this strategic crossing point was so important.
• Budou no Oka (Grape Hill): A hilltop park offering wine tasting of over 200 local wines, hot spring baths, a restaurant, and sweeping views of the Kofu Basin.

How to Get There

Iwai Bridge is accessible from JR Katsunuma Budokyo Station on the Chuo Main Line. The walk takes approximately 25–30 minutes, mostly downhill through pleasant vineyard scenery. Alternatively, take the Koshu City community bus (Budou Course 2 or Wine Course 2) and alight at the "Iwai-bashi" stop — about a 10-minute ride from the station at a flat fare of 300 yen. By car, the bridge is about 5 minutes from the Katsunuma Interchange on the Chuo Expressway. The bridge is always open and free to visit.