The Rosalia Railroad Bridge was built by the Chicago, Milwaukee, St. Paul and Pacific Railroad in 1915 to replace an earlier timber trestle. The bridge was designed as a concrete arch, unusual for a railroad bridge, because it crosses the Northern Pacific Railroad tracks, a state highway, and is visible from Steptoe Battlefield State Park. The railroad wanted an impressive-looking bridge. The viaduct consists of two spans, separated by an embankment. East of the 334-foot (102 m) embankment there is a 114-foot (35 m) span crossing over the Northern Pacific tracks. To the west is a 502-foot (153 m) span that crosses Pine Creek, railroad tracks, and the highway.