Lanesboro Trail Bridge (West)

Located on the west side of Lanesboro, this unique through truss bridge crosses the South Branch Root River. The original bridge at this location was likely a timber truss bridge. In 1910, the wooden bridge was replaced with a secondhand span. The truss was originally fabricated in 1888 as part of a bridge across the Des Moines River west of Madrid, Iowa. When that bridge was replaced in 1909 by a heavier bridge, the spans were reused at other locations. The eastern span (span #3) was reused at Bridge #AA-930 across the Grand River near Mobridge, South Dakota, and has since been removed. The middle span (span #2) was reused at Bridge #M-188 across the Chippewa River in Eau Claire, Wisconsin., where it continues to serve as a trail. The western span (span #1) was relocated to this location.

The bridge features a pin connected, 6-panel Warren through truss span, set onto stone abutments from the previous bridge. The use of pinned connections in Warren spans was exceptionally rare, both for roadway and railroad bridges. It is currently unknown why a pinned Warren span was used instead of a traditional Pratt span. One theory is that this span was an experimental design by Charles L. Strobel. Strobel worked with Keystone Bridge Company during the 19th Century, which is presumed to have fabricated this bridge. Strobel would later go on to start his own firm, building numerous notable steel bridges throughout the United States.

Reusing spans was a common technique for railroads looking to save money. Often, when a steel or iron span became too light for mainline traffic, it could be relocated to a branch line and have sufficient strength to carry the necessary loads. It appears that little alterations were made when this bridge was relocated, and it still appears to retain the original design. Overall, this bridge appears to be in good condition, with little significant deterioration noted. The author has ranked the bridge as being highly significant, due to the unique design and history.