Cold Spring Canyon Arch Bridge, Steel arch road bridge in Santa Ynez Mountains, US.

Cold Spring Canyon Arch Bridge is a steel arch road bridge on State Route 154, linking Santa Barbara with Santa Ynez. Its deck reaches 400 ft (122 m) above the canyon floor, making it California's highest arch bridge and largest steel arch bridge. The arch supports the deck rather than spanning the full valley width.

The bridge was completed in 1964 and combined steel construction techniques from American Bridge Company with innovative design solutions for steep mountain terrain. It later earned recognition as a Historic Civil Engineering Landmark for its engineering significance.

The location sits near Cold Spring Tavern, a former stagecoach stop from the 1800s, which reflects how transportation evolved in California's mountain regions. The bridge stands as a symbol connecting isolated communities and shows how engineering made settling these areas possible.

The bridge carries State Route 154 between Santa Barbara and Santa Ynez, with an average of 13,500 vehicles crossing daily in 2009. Cold Spring Tavern, a former stagecoach stop, sits about 600 m south of the west base in the canyon below, reached via Stagecoach Road, a stub of Old San Marcos Pass Road that meets SR 154 at Camino Cielo and Paradise Roads.

The 9.5 ft (2.9 m) inwardly-curved mesh fence installed in March 2012 cost $3.2 million and followed 55 recorded suicides since the bridge opened. A Santa Monica man died from the bridge six months after the fence went up, in September 2012.