The bridge, carrying Interstate 5 on its upper deck and Union Pacific Railroad on its lower deck, was built in 1942 as part of the construction of the Shasta Dam/Shasta Lake reservoir system.

[2] With a height of 500 feet (150 m) above the old Pit River bed, it is structurally the highest double decked bridge in the United States; however, today the bridge sits only about 40 feet (12 m) above the water when Shasta Lake is full.

At the time it was built, the highway on the bridge was signed as U.S. Route 99 and the rail line was owned by Southern Pacific.

The Coast Starlight, the passenger train line operated by Amtrak that runs between Los Angeles and Seattle, also uses the bridge.

[1] The Pit River Bridge was the subject of the 1954 Pulitzer Prize for Photography winner entitled "Rescue on Pit River Bridge", taken by Virginia Schau.