Why One Los Angeles Freeway Has Three Names and Locals Still Understand It

LOS ANGELES: Ask for directions near downtown and someone may tell you to take the 110, the Harbor Freeway or the Pasadena Freeway. They can be describing the same continuous road, depending on which direction you are going and how long they have lived here. It sounds like a prank the city plays on newcomers. There is a logic to it, though, and learning that logic makes Los Angeles feel much easier to read.

The first clue is that a route number and a freeway name do different jobs. The number belongs to a larger highway system. The name usually describes a segment, destination, landscape or person associated with one piece of that system. South of downtown, Interstate 110 runs toward San Pedro as the Harbor Freeway. North of the interchange with U.S. 101, State Route 110 continues toward Pasadena as the Arroyo Seco Parkway.

Los Angeles drivers often navigate with route numbers, destination names and historic freeway names at the same time. Image: Tony Webster / CC BY 2.0

That split is not merely local slang. Caltrans identifies the northern section between Route 101 and Pasadena as an 8.2-mile stretch of Route 110 known as the Arroyo Seco Parkway. Its history is unusually important. The road was dedicated in 1940 and is recognized by Caltrans as California’s first freeway. Early drivers experienced a landscaped parkway whose curves, short ramps and setting beside the arroyo feel very different from a modern interstate.

The road’s public identity changed with the city around it. The Arroyo Seco Parkway became widely known as the Pasadena Freeway during the postwar freeway era, when destination-based names helped drivers understand an expanding network. Its original name was restored officially decades later, but “Pasadena Freeway” never vanished from conversation. People pass down directions the way families pass down recipes: the wording survives even after the label changes.

The southern half carries another geographic promise. “Harbor Freeway” tells drivers that the route links central Los Angeles with the port area. The number 110 keeps the two halves connected on maps and signs, while the names preserve two different stories. One points toward shipping and industry. The other remembers a scenic corridor between Los Angeles and Pasadena. A single shield cannot communicate all of that.

Here is a quick local test. If someone says “the 110” with no other clue, look at the destination. Downtown to San Pedro usually means the Harbor Freeway. Downtown to Pasadena means the Arroyo Seco Parkway, though plenty of Angelenos will still say Pasadena Freeway. If they mention the Four Level, they mean the famous interchange near downtown where the 110 meets the 101. Context is doing as much work as the official signs.

Los Angeles is full of similar overlaps. Freeways acquired destination names, memorial names and state or federal route numbers at different moments. Some names cover only part of a numbered route. Others remain popular long after signs emphasize the number. This is why giving directions by name can reveal where a person started, which neighborhood they know best and even which era taught them to drive.

You can turn the lesson into a passenger game. Before the navigation voice announces the next move, guess whether the upcoming sign will use a number, a destination or a historic name. Then ask which clue would make the most sense to someone without a phone. The game sounds silly, but it reveals how much local knowledge modern directions normally hide behind a blue line.

The safest navigation habit is wonderfully unglamorous: confirm the route number, direction and next major interchange instead of trusting one name. “110 north past the 101” is clearer than “take the Pasadena” when your passenger has never heard the older label. The same principle helps when using Metro for major Los Angeles events. A familiar local phrase is useful only when everyone in the group is picturing the same place.

The naming puzzle is part of the city’s charm because it turns transportation into living history. Angels Flight’s surprisingly big backstory does something similar on a much smaller scale. In both cases, infrastructure becomes easier to remember once it stops looking like anonymous concrete. The next time the 110 seems to change identity beneath your wheels, nothing has gone wrong. You have simply crossed from one Los Angeles story into another.