Santa Fe Arroyo Seco Railroad Bridge, Railroad bridge in Highland Park, Los Angeles, California.

The Santa Fe Arroyo Seco Railroad Bridge is a steel span more than 710 feet (220 m) long that crosses the Arroyo Seco Parkway at a height of over 56 feet (17 m) in Highland Park. It carries the tracks of the Metro A Line over the lower Arroyo Seco, the watershed canyon running down from the San Gabriel Mountains.

The Santa Fe Arroyo Seco Railroad Bridge was built in 1896, replacing an 1889 wooden trestle designed by Santa Fe chief structural engineer Fred T. Perris for the Southern California Railway, itself a successor to the Los Angeles and San Gabriel Valley Railroad's 1885 trestle. Mainline rail service ended in 1994; in the late 1990s the bridge was retrofitted for the Metro Gold Line, opened July 26, 2003, and the A Line has run on its tracks since the Regional Connector opened in June 2023.

The bridge was declared Los Angeles Historic-Cultural Monument No. 339 on January 22, 1988, after a campaign led by the Highland Park Heritage Trust and Charles J. Fisher. The monument plaque marks a structure that has carried trains over the Arroyo Seco since 1896.

The bridge can be viewed from several vantage points along the Arroyo Seco Parkway and offers good opportunities for photographs from a distance. The actual bridge deck is not accessible to the public, so viewing happens from nearby ground level or from passing vehicles.

The 1896 steel span replaced an 1889 wooden trestle designed by Santa Fe chief structural engineer Fred T. Perris, which itself replaced an 1885 trestle of the Los Angeles and San Gabriel Valley Railroad. Mainline rail service ended in 1994, yet the bridge was retrofitted in the late 1990s for the Metro Gold Line, opened July 26, 2003.