State Route 110 (California)

State Route 110 (California) is a north–south state highway in Los Angeles County linking the Port of Los Angeles at San Pedro with downtown Los Angeles and continuing to Pasadena. The route consists of the southern Harbor Freeway and the northern historic Pasadena Freeway, forming one of the oldest highway corridors in California. It serves major ports, commercial districts, municipal centers and cultural sites across San Pedro, Wilmington, Downtown Los Angeles, South Los Angeles, Highland Park and Old Pasadena.

Route description

The route begins at the San Pedro waterfront near the Port of Los Angeles and travels north as the elevated Harbor Freeway through Wilmington and adjacent to Terminal Island. It intersects major corridors including I‑405 connectors and junctions with SR 47 near Willowbrook and Commerce. Entering South Los Angeles, the freeway crosses beneath access points to Los Angeles Memorial Coliseum, University of Southern California, and meets I‑10 near Exposition Park. Proceeding into Downtown Los Angeles, the route intersects the Santa Monica Freeway and provides ramps to I‑5 and US 101, skirting landmarks such as Los Angeles Union Station and Walt Disney Concert Hall. North of downtown the highway transitions to the historic Pasadena Freeway—a surface-level, scenic roadway that passes through Lincoln Heights and Highland Park before terminating near Old Pasadena at SR 210 and city streets near Colorado Boulevard. The corridor provides multimodal connections to Metro Rail lines including the A Line and the E Line at transfer points near Downtown Los Angeles and serves bus routes operated by Metro.

History

The corridor traces origins to early 20th‑century parkways; the northern segment opened as the Pasadena to Los Angeles highway and later became the first freeway in the western United States, originally called the Arroyo Seco Parkway and opened in 1940. The route was designated as part of the state highway system in the 1930s, with alignments tied to earlier US Route 66 segments and to the development of the Port of Los Angeles and Harbor Department facilities. Postwar expansion and the Interstate era spurred construction of the elevated Harbor Freeway in the 1950s and 1960s, integrating ramps for I‑10 and US 101. The freeway corridor was the focus of major civil works following urban planning initiatives by figures associated with county planning and controversies over right‑of‑way affecting neighborhoods such as Bunker Hill. The Arroyo Seco Parkway received historic recognition from organizations including National Register of Historic Places and American Society of Civil Engineers as an engineering landmark. Environmental and community advocacy groups, including local chapters of national organizations like Sierra Club and neighborhood coalitions in Highland Park, influenced preservation efforts that led to retention of the scenic northern alignment rather than conversion to a full modern freeway.

Major intersections

Service interchanges and connections along the corridor include junctions with SR 1 near Wilmington, ramps to I‑405 via connecting arterials, the interchange with I‑10 / US 101 near Downtown Los Angeles, connections with I‑5 and the Golden State Freeway corridor, and northern termini linking to SR 134 and SR 210 near Pasadena. The route serves as a primary freight artery to terminals managed by the Port of Los Angeles and links to rail freight facilities at Commerce and Elysian Valley intermodal locations. Numerous local streets provide access points to civic landmarks such as Los Angeles Memorial Coliseum, Union Station, Walt Disney Concert Hall and California Institute of Technology via Colorado Boulevard and adjacent arterials.

Related routes and designations

The highway is associated with named segments: the southern Harbor Freeway and the northern Arroyo Seco Parkway / Pasadena Freeway. Portions of the corridor overlap or interface with federal and state numbered highways including US 101, I‑10, I‑5, SR 47, SR 1, SR 134 and SR 210. The Arroyo Seco Parkway has been designated a National Scenic Byway and listed in registers maintained by the National Park Service and heritage organizations. Local jurisdictions such as the City of Los Angeles and the City of Pasadena administer adjacent roadway segments and collaborate with agencies including the California Department of Transportation and Metro on operations.

Future plans and improvements

Planned projects affecting the corridor involve seismic retrofits, interchange modernization, and multimodal upgrades coordinated by Caltrans District 7 and Metro. Initiatives include improvements to freight access serving the Port of Los Angeles, active transportation enhancements near Old Pasadena, and transit priority projects connecting to Union Station and Downtown Los Angeles. Proposals from regional planning bodies such as the Southern California Association of Governments outline scenarios for congestion mitigation, emissions reduction aligned with California Air Resources Board targets, and potential managed lanes or interchange reconfigurations informed by environmental review under California Environmental Quality Act processes. Community groups and preservationists continue to shape outcomes for the historic Arroyo Seco Parkway segment through advocacy with entities like the National Trust for Historic Preservation and local preservation commissions.

Category:State highways in California Category:Transportation in Los Angeles County, California