Badger State Trail - Cannonball Path Bridge

Located in Fitchburg, this deck plate girder bridge carries the former Illinois Central Railroad Madison Branch over the former Chicago & North Western Railway secondary line between Milwaukee and southwest Wisconsin. When the Chicago, Madison & Northern Railroad extended their line to Madison, a crossing of the C&NW was required south of the city. South of Madison, the CM&N climbed a large grade, before descending into Madison. The chosen crossing point was known as "Summit", and was to be near the top of the large grade. Built in 1887, the bridge consists of three 52-foot deck plate girder spans, set onto steel bent towers and stone abutments and footings. The superstructure uses a typical design for the era, with shallow girders constructed with an open deck. The towers are constructed of built-up beams, with a solid plate on the outside and V-lacing on the inside. The beams are connected by a lattice beam at the top and at the base. The abutments use a standard U-shaped design, with no wing walls. Stone for the substructures was quarried at an unknown location, and has a yellowish color. It is believed that Union Bridge Company fabricated the superstructure at their Buffalo, New York shops; while contractor Ryan & McDonald constructed the substructure. Deck plate girder bridges were commonly used by railroads, as they were durable and easy to construct. Since the initial construction, the structure has seen few alterations. A wooden deck and railings were added to the bridge in the early 2000s, and the structure now carries the Badger State Trail over the Cannonball Path. This location has become known as the "Velo Underround", and is one of the only grade-separated bike path interchanges in the area. Overall, the bridge appears to be in fair to good condition, with no significant deterioration noted. The author has ranked this bridge as being moderately significant, due to the age.