Freeways of Los Angeles

Everything you always wanted to know about Los Angeles freeway history and engineering but were afraid to ask. We cover local state highways too.

[Freeways of Los Angeles @FreewaysLA]

Common abbreviations:

CA - California (State Route)
c. - Circa
DOH - Division of Highways
EB - Eastbound
NB - Northbound
OC - Overcrossing
OH - Overhead
POC - Pedestrian Overcrossing
SB - Southbound
UC - Undercrossing
UP - Underpass
US - United States Route
WB - Westbound

[Freeways of Los Angeles @FreewaysLA]

1953 - Santa Ana Fwy (US-101) near Alameda St & Union Station. SB roadway under construction at left (LA Times Collection).

SB-101 traffic on NB lanes; NB-101 detoured to Alameda St off-ramp at right.

Civic Center skyline in background. US-101 became Hollywood Fwy at Spring St.

[L.A. Dork @la_dorkout]

The freeway tunnels near Dodger Stadium, built from 1931-1935, were originally the Figueroa Street Tunnels, serving two-way traffic.

By 1943, they were converted to one-way northbound traffic for the newly opened Arroyo Seco Parkway. (Southbound lanes were cut thru the hills.)

[Freeways of Los Angeles @FreewaysLA]

1952 - Looking NW over Santa Ana Fwy (then US-101, now I-5) construction at present-day location of I-710 interchange (ACSC Collection).

Eastern Ave OC at center; Olympic Blvd (CA-26) OC in background. Telegraph Rd-Marianna St on-ramp under construction between overcrossings.

[Freeways of Los Angeles @FreewaysLA]

1943 - from Freeways for the Region publication.

[Freeways of Los Angeles @FreewaysLA]

1951 - State Division of Highways Layout and Profile "As Built Plan" of Hollywood Parkway between Edgeware Rd and Boylston St in Los Angeles (DOH As Built Archives). Several items of interest:

- All early freeways were called parkways, even those built in urban areas.

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[Freeways of Los Angeles @FreewaysLA]

original ground line that gives a visual indication of excavation (cut) or embankment (fill) required, as noted by calculated quantities of each shown along the bottom.

- State right of way lines are annotated "R/W".

- The ever-present north arrow at right.

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[Freeways of Los Angeles @FreewaysLA]

This includes curve alignments and bearings/lengths of tangent (straightaway) lines. Pavement types and depths are also indicated. Nearby bench marks are noted for the surveyor.

- The profile plan (lower) shows vertical alignment (grades and vertical curves) and includes an

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[Freeways of Los Angeles @FreewaysLA]

@BrianD253 Fair enough, but understand that need for the safety features were not anticipated but its need was soon realized after freeway opening.

[Freeways of Los Angeles @FreewaysLA]

1941-March-27 - Looking easterly over newly constructed Arroyo Seco Pkwy (then US-66, now CA-110) at Fair Oaks Ave OC (ACSC Collection).

Due to lack of engineering experience in designing freeways, note deficient safety features:

- narrow lanes

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[Freeways of Los Angeles @FreewaysLA]

For the record, on opening day, the posted speed limit for the Arroyo Seco Pkwy was 45 mph.

[Freeways of Los Angeles @FreewaysLA]

- short acceleration and deceleration lanes
- no median barrier
- no shoulders for disabled vehicles
- no shoulders for flooded areas
- no protection at bridge abutments

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[Freeways of Los Angeles @FreewaysLA]

Feb 1967 - New freeway guide signs at various Los Angeles area freeways. Captions under each picture provide details.

Note that some signs still provided freeway names (ACSC News Pictorial).

[L.A. Dork @la_dorkout]

In the '60s, freeways were measured by economics --increased productivity, dollars brought in, and how they were 3x less deadly than highways. These old metrics yielded today's LA cityscape.

Quality of life, pollution, etc. were ignored until the '70s, when most were in place.

[Freeways of Los Angeles @FreewaysLA]

- [LA] River Fwy = Long Beach Fwy (I-710)

- Colorado Fwy = Ventura Fwy (CA-134) & Foothill Fwy (CA-210)

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[Freeways of Los Angeles @FreewaysLA]

1951-April-23 - Los Angeles Times map of existing and proposed area freeways.

Courtesy of Jorge Mena Jr of "You know You Are From Old School Pasadena When . . ." Facebook group.

Some of the old and current names:

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[Freeways of Los Angeles @FreewaysLA]

- Sepulveda Fwy = San Diego Fwy (I-405)

- Olympic Fwy = Santa Monica Fwy (I-10)

- Santa Monica Fwy = Beverly Hills Fwy (CA-2)

- San Fernando Fwy = Golden State Fwy (I-5)

- Ramona Fwy = San Bernardino Fwy (I-10)

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[Freeways of Los Angeles @FreewaysLA]

@CED_LD_Guy FYI:
The Century Fwy (I-105) opened around 1992. The Foothill Fwy (CA-210) extension was completed around 2002. The Santa Ana Fwy (I-5) reconstruction was completed around 2016.

[Freeways of Los Angeles @FreewaysLA]

1964 - Model and cross-section of proposed Beverly Hills Fwy (CA-2). Freeway would be constructed under Santa Monica Blvd (US-66). Community opposition doomed this idea (DOH Archives).

Camden Dr & All Saints Episcopal Church in foreground. Beverly Hills City Hall in background.

[Freeways of Los Angeles @FreewaysLA]

@four2oderek Yes