The Sundial Bridge in Redding is one of only two bridges in the United States designed by world-renowned architect Santiago Calatrava. It is a cantilever spar cable-stayed pedestrian bridge that spans the Sacramento River and forms the world's largest sundial. The 217 foot pylon of the bridge points due north at a cantilevered angle allowing it to serve as the gnomon of a mammoth sundial that casts its shadow on a large dial plate on the bridge's north end. The tip of the shadow moves at a speed of approximately one foot per minute so the Earth's rotation can be seen with the naked eye! The bridge is over 700 feet long and crosses the river without touching the water. The deck is surfaced with translucent glass which is illuminated from beneath and glows aquamarine at night. This decking casts less of a shadow on the river below and along with the fully suspended surface minimizes impact on the delicate salmon spawning grounds in the river.