Route 110, consisting of State Route 110 and Interstate 110 , locally referred to as the one ten, is a state highway in the Los Angeles area of the U.S. state of California, built to freeway standards. The entire length of I-110 , as well as SR 110 south of the Four Level Interchange with US 101, is the Harbor Freeway, and SR 110 north from US 101 to Pasadena is the historic Arroyo Seco Parkway, the first freeway in the western United States. The entire Route 110 connects San Pedro and the Port of Los Angeles with Downtown Los Angeles and Pasadena. I-110 is one of two 3-digit interstate designations to appear on opposite coasts, with I-280 in California and New Jersey being the other.Route descriptionThis route is part of the California Freeway and Expressway System.The Harbor Freeway begins at Gaffey Street in San Pedro, where it then travels mostly due north to the Santa Monica Freeway (Interstate 10) at a point south of downtown Los Angeles, where it becomes signed as State Route 110. I-110 is primarily within the city limits of Los Angeles, running right through South Central Los Angeles and the Harbor Gateway, a two-mile (3 km) wide north–south corridor that was annexed by the city of Los Angeles specifically to connect San Pedro, Wilmington and the Port of Los Angeles with the rest the city.