Submerged bridge connecting people living in the Shimanto River basin

Shimanto River and Submerged Bridge

The Shimanto River has its source in Mt.Irazuyama, Tsuno Town, Kochi Prefecture. The total length of the river is 196 km, and it empties into the Pacific Ocean at its final point, Shimoda, Shimanto City, 196 km from its source.

Near the estuary that flows into the Pacific Ocean

meandering river

The Pacific Plate is located on the ocean floor of Kochi Prefecture.

The Shimanto River, which was supposed to flow southward from its source in the mountains, has been pushed northward every time it is pushed up by the Pacific plate due to tectonic movements on the ocean floor. The river meandered as it was pushed up from south to north many times.

large meandering river

A meandering river created a village

As the river meandered, flat land was created on both sides of the river, and villages were born. ``Ferryboats'' came and went between villages that were born on both sides of the river, and boats and ``bamboo floating bridges'' connected people. Due to the abundance of water and the formation of wide rivers and riverbeds, not only fisheries such as fire fishing and cast nets, but also transportation and forestry, which transports wood cut from the mountains by boat, are carried out, and people and rivers are connected. The close relationship between the two shaped the landscape.

fire fishing

A raging river blocks people's movement

The Shimanto River is also famous for being a raging river, and is prone to flooding and flooding throughout the year. The ``fertility boats'' and ``bamboo floating bridges'' that connect villages were unable to operate when the river flooded, or were washed away by the increasing force of the Shimanto River many times. The movement of people between villages was often blocked.

Comparison of subsidence during normal times (left) and when the water rises (right)

A submerged bridge is born

People living in the basin wanted a bridge that could withstand rising water and flooding. The current shape of the submerged bridge was created by having the strength to withstand driftwood without resisting a raging river, and the flexibility to ``negate'' muddy currents. The bridge has no railings and has rounded edges. It was designed with the assumption that it would sink if the river rose.

rounded edges

Submerged bridge spanning the Shimanto River

Approximately 48 submerged bridges are built along the 196km long flowing path. The 48 submerged bridges have been a way of life connecting people between villages since ancient times. From the submerged bridge, you can see the lives and livelihoods of the people living in the basin. People's lives that depend on the river, such as fishing, forestry, agriculture, and tourism, still continue today. The characteristics and sights of submerged bridges vary depending on the location, and they entertain both those who see them and those who cross them.

Submerged bridge with various features

Sada sinking bridge

Sada Submerged Bridge is located near the downtown area of ​​Shimanto City. At Sada Submerged Bridge, which spans the downstream area, houseboats take tourists on board, and boatmen tell them about the history and culture of the Shimanto River. In early summer, fishing equipment for ayu, river shrimp, and eel are set up, allowing you to catch a glimpse of river fishing. Once on board, tourists' viewpoints are close to the surface of the river, and they can clearly see the fish swimming in the clear river and the stone moss. The sound of the river and the chirping of birds echoing from the mountains on both sides relaxes your tired mind.

Sanri Submerged Bridge

At Sanri Submerged Bridge, where houseboats come and go, people from children to adults can be seen enjoying canoeing and SUP. On a clear summer evening, the submerged bridge is illuminated by the setting sun, bathing it in orange. A sunken bridge where you can enjoy a nostalgic view of Japan.

Iwama sinking bridge

This sinking bridge became popular on TV and in commercials. There is a large cherry tree in the parking lot along the national highway, and in spring you can see the submerged bridge through the cherry blossoms and rape blossoms in full bloom. There is a monument to the song ``Shimantogawa'' sung by Hiroshi Miyama, an enka singer from Kochi Prefecture, and audio equipment, and the scenery and enka will entertain fans of the singer as well as visitors.

A story told by a submerged bridge

A submerged bridge where you can enjoy the unique scenery of each season. Whether it's sunny or raining, it entertains visitors with its various expressions. Why not come and see for yourself the 48 stories that span the Shimanto River?