Colorado Street Bridge, Deck arch bridge in Pasadena, United States.

The Colorado Street Bridge is a reinforced-concrete road bridge that carries West Colorado Boulevard across the Arroyo Seco in Pasadena in a long curve. Its main span is a series of nine parabolic arch ribs of varying widths, flanked at each end by three narrow round arches, with slender piers and spandrel columns rising to the deck. The deck runs about 45 m above the valley floor and slopes 2.65% from east to west; the balustrades are broken above each pier pair by small balconies with benches between two lamp standards.

Construction finished in 1913, connecting neighborhoods separated by a canyon that had been difficult to cross. The bridge carried Route 66 traffic for four years starting in 1936, before the highway alignment changed.

Locals once called it "Suicide Bridge" after dozens of jumps in the early 20th century; by 1937, 87 people had died there. Each summer the bridge closes for the "Celebration on the Colorado Street Bridge" festival, hosted by the preservation group Pasadena Heritage. The 1984 album Songs from Suicide Bridge by Eric Caboor and David Kauffman takes its name from the span.

The best views of the arches come from trails at the bottom of the canyon, reached via West Holly Street and North Arroyo Boulevard. Pedestrians crossing on the roadway should use the narrow sidewalk and stay alert to passing cars.

The bridge's curve was not decorative: engineers bent the alignment so the footings could rest on firmer ground than a straight crossing would have reached. The deck also falls about 2.65 percent from east to west, following the differing heights of the two banks.