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Duluth Aerial Lift Bridge Photos

Although originally designed and currently configured as a vertical lift bridge, the Aerial Lift Bridge in Duluth began life as an aerial transfer bridge, an extremely rare type inspired by the only other such structure in the world – a suspended car bridge at Rouen, France.

The need for a bridge here first arose in 1871, when Duluth residents dug through the narrow slit of land known as Minnesota Point to create a harbor at the head of the Great Lakes. As advantageous as the shipping canal was for the city, it left citizens on the Point cut off from the mainland. In 1892 Duluth held a competition for a bridge design that would enable residents to cross without interrupting traffic in the shipping lane. The winning design, engineered by John Alexander Low Waddell, would have been the world’s first high-rise vertical lift bridge. But the Duluth project was cancelled before construction began and Waddell’s design was later built in Chicago. In 1905 Duluth finally built its bridge – an aerial transfer bridge with a huge gondola that could carry more than 60 tons of traffic, from pedestrians and horse-drawn wagons to automobiles. The 300-foot crossing took one minute to complete and was made every five minutes when traffic was heavy.

In 1929 the bridge was modified to accommodate a growing population on the Point and increasing tourist traffic. The gondola was removed, the height of the top span increased and structural supports incorporated into the towers to carry the counterweight roadway. This remodeling – coincidentally designed by a successor to Waddell’s engineering company – transformed the bridge into a vertical lift bridge much like the one originally conceived in 1892.