Kachidoki Bridge

A 246-metre steel road bridge completed in 1940 on the Sumida River. Its central span is Japan's only Chicago-style double-leaf bascule bridge, last opened in 1970. Designated an Important Cultural Property in 2007.

Use

Office tower

Area

Chuo City

Completed

1940

Developer

City of Tokyo

Architect

Masaru Atagi (City of Tokyo engineer)

“The Orient’s Finest Movable Bridge” on the Sumida

Kachidoki Bridge spans the Sumida River where Harumi-dori crosses the waterway between Tsukiji and Kachidoki in Chuo City. Completed in June 1940, it stretches 246 metres in three spans: a central Chicago-style double-leaf bascule measuring 51.6 metres — the longest movable span in Japan — flanked by two through tied-arch side spans. The City of Tokyo engineer Masaru Atagi led the detailed design, while the bascule machinery was fabricated by Kawasaki Sharyo, Yokogawa Bridge, and Ishikawajima Shipbuilding, an entirely Japanese undertaking.

At its opening, the bridge lifted its two central leaves as many as fifty times a day, each opening lasting about twenty minutes to allow large vessels to pass. The spectacle drew crowds of curious Tokyoites, and the bridge earned the sobriquet “the Orient’s finest movable bridge.”

The Bridge That Stopped Opening

In 1964, the fixed Tsukudajima Bridge opened upstream, diverting most marine traffic and removing the practical need for Kachidoki’s bascule. Simultaneously, the postwar motorisation boom brought surging road traffic onto the bridge, making each opening more disruptive. On 29 November 1970, the leaves lifted for the last time. Since then the bridge has stood fixed, and its movable heart has been silent for more than half a century.

Despite the stillness, the bridge’s heavy arch ribs and portal frames retain their quiet presence over the river. In 2007 it was designated an Important Cultural Property alongside Kiyosu and Eitai bridges — the first road bridges under prefectural management to receive that status in Japan. The bascule machinery is also recognised as a Mechanical Engineering Heritage by the Japan Society of Mechanical Engineers.

Summary

Completed in 1940 and spanning 246 metres, Kachidoki Bridge remains Japan’s only surviving Chicago-style double-leaf bascule bridge — an exceptional specimen of early Showa-era civil engineering now protected as an Important Cultural Property.

Walk across the bridge from the Kachidoki side and the riveted steel arch curves overhead as a riverside wind pushes through. Looking west, the towers of Park Tower Harumi and Deux Tours Kachidoki frame a waterfront that has changed beyond recognition since 1940; yet the bridge itself, unchanged and unmistakeable, holds the older scene in place. The Tsukishima monja restaurant strip makes a natural starting point for a Sumida waterfront walk that ends here.