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Shimanto Sink Bridges — Drive Over, Not Under

Published: Jun 3, 2026

Updated: Jun 3, 2026

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Shimanto Sink Bridges — Drive Over, Not Under

Shimanto Sink Bridges — Drive Over, Not Under 2

The Shimanto River is crossed by 47 chinkabashi — low-slung, railing-free concrete bridges designed to be submerged during floods. The name means 'sink bridge,' and the design philosophy is simple: rather than build tall, expensive bridges that might be destroyed by typhoon-driven floods, build low, simple spans that let water pass over them. When the river rises, the bridges disappear underwater for days; when it recedes, they emerge unscathed.

Driving or cycling across a chinkabashi is a unique experience — the road surface is barely a meter above the river, there are no railings, and the sensation is of driving on the water itself. The most famous and photogenic is Iwama Chinkabashi, a 120-meter span with views upstream to forested hills and downstream to rice paddies. Other notable bridges include Sada Chinkabashi (291 meters, the longest) and Katsuma Chinkabashi (the lowest and most flood-prone).

Opening Hours

Bridges and river access 24 hours. Shimanto City Tourism Center (e-bike rental): 9:00–17:00. Check bridge flood status before visiting — posted online and at the tourism center.

Closed: Bridges close automatically when the river floods (no permanent closure, but seasonal flooding July–September can submerge bridges for 24–48 hours after heavy rain). Tourism center closed Wednesdays.

Entrance Fee

Free access to all chinkabashi. E-bike rental ¥1,500/day from Shimanto City Tourism Center. Canoe tours ¥6,500/person (April–October). No parking fees at bridge viewing areas.

Best Season

May–June for fireflies along the riverbanks at dusk. October–November for clear skies and autumn foliage. Avoid July–September typhoon season when bridges may be flooded. Winter is quiet and photogenic.

Visit Duration

Drive to see 2–3 bridges: 2–3 hours. Full cycling route (20km, 3–4 bridges): 5–6 hours. Combine with a canoe tour for a full day on the Shimanto River.

Getting There

Access Information

Shimanto City area, accessible by car or bicycle (rental bikes in Shimanto City, ¥1,500/day). Iwama Chinkabashi is 15 min by car from Ekawasaki Station. Free access. Check flood status before visiting (available at Shimanto City Tourism Center).

Insider Guide

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**Safety notes:** Chinkabashi have no railings. Drive slowly (under 20 km/h). In rain or after heavy rain, bridges may be closed — never attempt to cross a flooded chinkabashi. Locals know this; touri