The Forsyth Bridge across the Yellowstone River in Forsyth, Montana is a Pennsylvania truss bridge which was built in 1905.

It was listed on the National Register of Historic Places in 1990.

[1] The bridge is important historically as the first bridge linking what is now the northern section of Rosebud County to its southern section; the nearest Yellowston River bridge crossing was in Miles City, about 45 miles (72 km) downstream.

The need for the bridge was deeply felt locally and was a major factor in the area's initiative to create the county, splitting the area off of Custer County so that this bridge would be built.

This article about a property in Montana on the National Register of Historic Places is a stub.