This is a bridge that I know very little about. It was built by the Chicago, Milwaukee, St. Paul, and Omaha Railroad, which became the Chicago & Northwestern, which is now the Union Pacific Railway. The bridge is still in operation, and it frequently opens and closes in the summertime.

This bridge is located in an area of the Saint Croix where sandbars naturally occur. The bridge is located close to the Minnesota shore, and connects to a long causeway built across a relatively wide part of the Saint Croix river. On the Wisconsin side, the causeway branches off in to two different wye-configurations. One branch of the second wye runs along the river short, crossing a dam that holds back a tributary of the river. The river crossing paths vary from 3,150 feet to as much as 4,550 feet. Only one path currently has rails, and that supports the UP mainline. That path is approximately 3,922 feet.

Each of the four paths coming out of the two wye junctions has a small bridge where it connects to the Wisconsin shore. Once such bridge is shown in a photo below.