Sundial Bridge at Turtle Bay

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Sundial Bridge

Official name	Sundial Bridge at Turtle Bay
Carries	Bicycles and pedestrians
Crosses	Sacramento River
Locale	Redding, California
Maintained by	Unknown
Design	Cantilever spar cable-stayed bridge
Longest span	unknown
Total length	700Ft
Width	23 ft
Vertical clearance	unknown
Clearance below	26 m
Opening date	July 4, 2004

The Sundial Bridge is a cantilever spar cable-stayed bridge that spans the Sacramento River in Redding, California (coordinates: 40°35'34.27"N 122°22'39.46"W). It was designed by Santiago Calatrava and completed in 2004 at a cost of US$23,000,000.

Similar to his earlier (1992) design (the Puente del Alamillo in Seville, Spain), this subtype uniquely does not balance the forces by using a symmetrical arrangement of cable forces on each side of the tower; instead it uses an angled cantilever tower loaded by cable stays on only one side. This requires that the spar resist bending and torsional forces and that its foundation resists overturning. While this leads to a less structurally efficient structure the architectural statement is considered dramatic.

This pedestrian bridge features a single 217 foot (66 metre) mast that serves as a sundial, which can be read in a garden to the north of the bridge. It connects the two sections of Turtle Bay Exploration Park, which leads to Turtle Bay Elementary.

The deck is surfaced with transparent structural glass, with a view of the water below as one crosses. The walkway and river are illuminated from beneath the deck at night. It is 700 feet (213 m) in length and crosses the river without once touching the water. The cable stays are not centered on the walkway but instead divide the bridge into a major and minor path.

The shadow cast by the bridge functions as a sundial, but is only accurate one day a year - the summer solstice. An additional but unintended feature of the bridge is that the pylons can be used to generate a sound effect similar to that of the imperial storm troopers' guns in Star Wars.