The line was a branch line meant to serve the river towns of Sauk City and Prairie Du Sac.
The CM&StP became the Chicago, Milwaukee, St. Paul & Pacific in 1915, with the nickname of the Milwaukee Road.
In 1941, the line was extended to serve the Badger Ammunitions Plant north of Prairie Du Sac.
The line was purchased in 1982 from the Milwaukee Road by the Wisconsin Western Railroad, which would
eventually be purchased in 1985 by the Wisconsin & Calument, a short line railroad which operated many
other lines in the Madison Area.
The WICT was purchased by Wisconsin & Southern in 1992, who operated this line until March 2002, when the northern truss span crossing the Wisconsin River began to shift.
The maintenance to stabilize the bridge failed, and the span was blown up.
A similar situation happened in late 2016, after trail talks finally succeeded. The remainder of the bridge was removed, and a new bridge will be constructed for trail use.
02/25/23
The eastern of two bridges across the Wisconsin River at Sauk City, this bridge now crosses a stagnant back channel.
Built in 1911, the bridge consists of secondhand steel and iron components. The main spans of the bridge are a pair of 150-foot 6-panel pin connected Pratt Through Trusses, originally built in 1891 as part of the Mississippi River Bridge at Hastings, Minnesota. In 1910, those trusses were replaced by the current approach spans.
In addition, the bridge is approached by a 45 foot "type B" girder on either side, and several trestle spans on the east side. The girders were originally fabricated in 1892 at Bridge #A-56, across the North Branch Chicago River between the Chicago suburbs of Edgebrook and Forest Glen.
Often, railroads would reuse steel spans to save costs, particularly on branch lines.
The entire bridge rests on concrete and timber substructures. At one time, a long trestle connected this bridge to the main channel bridge.
Overall, this structure appears to remain in relatively good condition. Plans have been made to convert this structure to trail use.
The author has ranked this bridge as being regionally significant, due to the age of the trusses and girders.
The photo above is an overview in early 2018.
| Upstream | Merrimac Rail Bridge |
| Main Channel | Sauk City Bridge |
| Downstream | Spring Green Rail Bridge |