Steel Bridge

The lower deck of the Steel Bridge is raised to let the sternwheeler 'Rose' pass. (Click the image to see a larger version)

The Steel Bridge is a double lift bridge across the Willamette River in Portland, Oregon. It currently carries Amtrak and cargo trains and a jogging path on its lower deck, and cars (Oregon Highway 1W / Oregon Route 99W) along with the MAX mass transit line on the upper deck. It was named for being the first major bridge constructed primarily of steel in Portland.

The bridge was opened in 1912, and it is the only known dual-lift bridge in the world. That means that the lower deck can be raised up to the upper deck independently of the upper deck. They can be raised together, when a large ship requires the extra clearance.