One of the most photographed landmarks in Duluth, or all of Minnesota for that matter, is the Duluth Aerial Lift Bridge. A clearance of 180 feet is attained when the span is completely raised. The span length is 386 feet and weighs approximately 900 tons! The bridge is very similar to the only other one of its kind in the world, which is in Rouen, France.
Aerial Lift Bridge History
The mammoth steel and cable structure was completed in 1905, making it over 100 years old and the oldest of all structural landmarks in the city. On June 6, 1973, the Aerial Lift Bridge of Duluth was entered in the National Register of Historic Places. It connects the “mainland” with Minnesota (or Park) Point, a five mile long sandbar. Initially, the bridge was called the Duluth Aerial Ferry Bridge. At that time, the bridge had a high clearance to let boats pass and a cable car attached to the underside of the top truss, and a few hundred passengers, wagons, and even automobiles could be carried back and forth across the canal in about one minute.
But then, with heightened demand due to additional automobiles, more people living on Park Point, and more tourism, the bridge needed an upgrade. Reconstruction began in 1929 and lasted only one year. In that time, a new flat deck was built to span the length of the bridge. Because the deck was to be lifted for boats, the top span was raised so that the big ships could still use the canal. There was also work done on both sides of the bridge to support the added weight and dynamics. With all these changes and a usable road across the bridge, its name changed to the Aerial Lift Bridge.
The Duluth Bridge is operated 24 hours a day, with skilled people at the helm. The bridge is raised and lowered for iron ore and cement ships, sailboats, and excursion tour boats. In the busy seasons of spring and summer, the bridge averages 26 lifts a day. Decades ago, pedestrians were able to ride on the bridge when it was raised. But, this was outlawed in the early 1980s after a horrible accident that claimed the life of a woman when she was crushed by the steel bridge.
The bridge operation is primarily through electric power derived from storage batteries that are charged by generators. If power lines fail, the generators can be operated by a diesel engine. There are two 450 ton concrete block weights on each end, lifted by electronic pulleys to raise and lower the bridge. It is an incredible feat, and a very good reason in itself to come to Duluth to watch the whole operating process.
The ship canal piers were rehabilitated in 1985 with steel pilings and new concrete caps. The elements of furious Lake Superior storms, ice fields, errant ships, and extreme temperature changes have created many structural problems. The bridge, as it is today, has been repainted three times. Every 18 years it gets a new set of 12 cables. There were flood lights added in 1968 and now has a wonderful golden hue at night when lit.
The North and South piers are photographed frequently by just about everyone who visits. It’s tough to leave with a bad shot of the bridge and surrounding area. Amazing pictures of the lift bridge in Duluth MN on postcards or in beautiful frames are not hard to come by in the Canal Park shops. Over the years, there have been hundreds of books and articles written about it. Local gift shops feature the Bridge in various forms, like key chains, knickknacks, puzzles and much more.
Watching a huge ship come through the canal under the Aerial Lift Bridge is an awesome thing to experience. The ships are really almost bigger than you could imagine and it’s just one of those things you have to see for yourself. If you have sensitive ears, a pair of earplugs wouldn’t be a bad idea either. It is customary for both the ships and bridge operators to greet each other with a series of horn blasts!