The Armstrong Creek Bridge is located on the edge of the Nicolet National Forest. It was manufactured in 1908 by the Hennepin Bridge Company, an important and prolific bridge builder in Minneapolis, Minnesota. This bridge originally carried what was then known as Highway 101 over Armstrong Creek. In the 1940s, the roadway (called Old 101 Road) was re-routed just west of the bridge and the bridge continued to serve pedestrians.

The Armstrong Creek Bridge is an example of a "full-slope," or "standard," Pratt pony truss bridge. The Pratt truss was the second-most numerous pony truss ridge type on Wisconsin roadways at one time. As late as 1981, the Armstrong Creek Bridge was one of 69 standard Pratt truss bridges remaining in the state. By 1997, the number of standard Pratt truss bridges in Wisconsin had fallen to eight. The Armstrong Creek Bridge is a three-span structure; the central span is the Pratt pony truss. It is a steel, pin-connected truss with four panels on each side. It is 50 feet long and carries a 16 foot wide deck. In 2007, the bridge was removed from its original site to accommodate the realignment of Old 101 Road. In 2010, the bridge was repaired, repainted, and installed on new piers adjacent to Old 101 Road. The south end of the structure is now pivoted about 20 feet east from its original site, with the placement of the north end unchanged. The Armstrong Creek Bridge continues to present a good and intact example of a vanishing resource: the standard, Pratt pony truss bridge.