Bixby Creek Bridge. Big Sur, California:

Bixby Creek Bridge, also known as Bixby Bridge, is a reinforced concrete open-spandrel arch bridge in Big Sur, California. The bridge is located 120 miles (190 km) south of San Francisco and 13 miles (21 km) south of Carmel in Monterey County along State Route 1. Prior to the opening of the bridge in 1932, residents of the Big Sur area were virtually cut off during winter due to the often impassable Old Coast Road that led 11 miles (18 km) inland. At its completion, the bridge was built under budget for $199,861 and was the longest concrete arch span at 320 feet (98 m) on the California State Highway System. It is one of the tallest single-span concrete bridges in the world and one of the most photographed bridges along the Pacific Coast due to its aesthetic design and location.

The engineers considered two alternatives to crossing the creek, either an inland route and a smaller bridge, or a coastal location and a larger bridge. The inland route necessitated a 890 feet (270 m) tunnel cutting though the Santa Lucia Mountains to a 250 feet (76 m) bridge upstream. The engineers selected the coast route, because it was safer, more scenic, and least affected the environment.

California state highway engineer C.H. Purcell and bridge engineer and designer F.W. Panhorst considered whether to build a steel or concrete span. A steel bridge would cost more to build and maintain, as the sea air would require expensive ongoing maintenance and painting. A steel bridge was also less in keeping with the natural environment. Using concrete reduced material costs and allowed more of the total cost to be paid to workers, which was a positive aspect of the design during the Depression. They chose concrete in part because it would not only reduce both construction and maintenance costs but would also echo the color and composition of the natural rock cliff formations in the area.

In 1937, after 18 years of construction and aided by New Deal funds and the use of convict labor, the paved two-lane road now known as State Route 1 was completed.

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