The Oi River Toll-Crossing System — Why There Was No Bridge

“You can cross Hakone’s eight ri even by horse, but the Oi River can’t be crossed, however hard you try” — an old travelers’ song put it that way, because for Edo-period travelers, the Oi River flowing through central Shizuoka Prefecture was one of the greatest obstacles on the road. The reason was simple: this river had no bridge and no ferry. Whenever the water rose, the river was immediately closed to crossing, and travelers were stranded at the post towns for days, sometimes longer, until the water went down.

Origins — Why No Bridge Was Ever Built

The river-crossing system known as “kawagoshi” is said to have begun in 1601, when Tokugawa Ieyasu established the tenma system of relay horses and manpower along the highways, with each post town required to keep a supply on hand. In 1696, official river magistrates and administrators were formally appointed, establishing kawagoshi as an independent system in its own right. There was only one way to cross the river: paying a professional porter, called a kawagoshi ninsoku, to carry you across on their shoulders or on a litter called a rendai. Both bridges and ferries were prohibited by the shogunate. The common explanation is that this was a military defense measure to protect Edo, but in fact, no record exists of the shogunate ever stating this explicitly, and the specific military purpose remains unclear in the historical record. Some hold the view that, since the kawagoshi system itself generated substantial employment and income for the post towns, the “defense” explanation may have simply been added after the fact to justify what was, in practice, a profitable arrangement.

River Tickets and Porters — A Price and a Class System Set by the Water

Even becoming a kawagoshi porter required climbing a strict hierarchy. Training began at age 12 as an apprentice; at 15 you became a “mizuiri,” gaining hands-on experience; and only once you were recognized as fully qualified were you formally admitted as a porter, at the New Year. Payment was made with tickets called “kawafuda,” and the price changed according to the river’s water level, measured fresh every morning. At the shallowest level, “matadoshi” (water up to the thighs), a single ticket cost about 48 mon (roughly the equivalent of over a thousand yen today). As the water rose toward chest height, the price climbed sharply, and once it exceeded roughly 136 centimeters, the river was closed entirely under a “kawadome” order, and no crossing was possible at any price. Travelers with money could hire several porters and cross quickly by litter; those without simply had to wait at the post town until the water dropped.

Current Conditions — Preserved as the Kawagoshi Historic Site

The kawagoshi system disappeared once bridges and ferries were finally permitted in the Meiji era. Today, the city of Shimada preserves the old townscape as the “Oi River Kawagoshi Historic Site,” including the kawakaisho (the office that handled registration and payment) and the porters’ waiting houses, and it hosts events where visitors can dress in period costume and experience a mock river crossing. Far from a dangerous ruin, it is a maintained, welcoming tourist destination that can be visited safely.

Reflection — The Inequality Built Into the Choice Not to Build a Bridge

What draws our attention is that the Oi River’s kawagoshi system wasn’t simply an inconvenient way to cross a river — it was a device that made the class and wealth divide of the Edo period directly visible. Samurai and merchants with money could hire many porters and cross in comfort on a litter. Ordinary people with little travel money had no choice but to cling to a single porter’s shoulders, and when the river was closed, more than a few are said to have been stranded at the post towns, unable to afford lodging while they waited. Leaving that “deliberate inconvenience” of never building a single bridge in place, generation after generation, ended up creating an entire industry of porter employment and enormous income for the post towns of Shimada and Kanaya. This is only speculation, but it seems entirely plausible that the shogunate was well aware of this economic structure and simply used “defense” as convenient cover for never changing it. A single river that stopped people’s movement ended up supporting the livelihoods of many people, while also making many others suffer. We think the real unsettling core of this story lies in that twisted structure.

This, too, is nothing more than our own imagining, but records do show that river closures sometimes lasted for many days in a row, and among the travelers who ran out of money, it seems entirely possible that some became destitute at the post towns and, in the worst cases, lost their lives. The shogunate’s decision never to build a bridge or run a ferry wasn’t merely an inconvenience — at times, it must have been a decision heavy enough to determine whether a person lived or died. The Oi River, a single river that functioned as an engine of the local economy while also standing as a dividing line that decided the fate of anyone trying to cross it — that duality is where we find the true unease at the heart of this kawagoshi story.

Everyday Face — The Oigawa Railway’s Steam Locomotives

Right next to the historic site that tells the story of the “uncrossable” Oi River and its bridgeless, ferryless kawagoshi system, the Oigawa Railway’s steam locomotives still puff their way along the tracks today. The line between Kanaya Station and Senzu Station passes stations that feel like a trip back to the Showa era, along with scenic tea fields, offering a nostalgic ride even for those who aren’t train enthusiasts. After reflecting on the hardship of Edo-period travelers who once crossed this river on a porter’s shoulders, taking a leisurely ride on the steam train along the Oi River is a distinctly local way to enjoy the area.

A Note on Visiting

The Oi River Kawagoshi Historic Site is a heritage park maintained and open to the public by the city of Shimada, and it is not a dangerous location. Visiting hours and whether the costume experience events are running can change, so we recommend checking with the city of Shimada or the local tourism association before visiting.

Frequently Asked Questions

Q. Why was no bridge ever built over the Oi River?

A. It’s commonly explained as a defense measure for Edo, but no record shows the shogunate ever stating this directly, and the specific reason remains unclear. Some believe it was meant to protect the employment and income the kawagoshi system generated for the post towns.

Q. Can you still visit the kawagoshi historic site today?

A. Yes. It’s maintained by the city of Shimada as a heritage park, where you can see the old townscape and the kawakaisho building. Depending on the season, there are also events where you can experience a mock river crossing in period costume.

Q. Has KARASU CHANNEL filmed on location at the Oi River Kawagoshi Historic Site?

A. No, we have not filmed there yet; a visit is currently under consideration. Location footage for other haunted spots and kaidan stories can be viewed on KARASU CHANNEL (YouTube).