
During the 1920s, when the automobile started to become the primary method of transportation in America, the Donner Pass had an 18% incline in some areas, much too steep for cars. The state of California worked on building a new road over the famous Donner Pass in 1923 but was unsure how to best deal with the grade. Eventually, they decided on a concrete bridge that had both a curve and a gradual grade (the first of its kind to have both). The bridge was finished in 1926 at a full 241 feet long, materials for the bridge were taken from down near Donner Lake.
The bridge was fully restored in 1993 - adding a parking area and vista overlook.