Interstate 380

This past weekend I drove over twenty Californian highways with a good chunk of them being around the San Francisco Bay Area. The first highway I attempted was Interstate 380 from San Francisco International Airport west to I-280.

I-380 is an approximately 1.7 mile freeway connecting from US 101 at San Francisco International Airport west to I-280. The entire routing of I-380 is within San Mateo County and despite it's small size was conceived as a much larger route.

According to CAhighways.org the path of I-380 was first conceived as Legislative Route Number 229 in 1947 between US 101 Bypass west to US 101 in San Bruno.

CAhighways.org on LRN 229

LRN 229 was extended to CA 1 Pacifica in 1959 by the Legislature. While LRN 229 in it's original form was too small display on State Highway Maps it does appear in full scope by the 1960 addition.

1960 State Highway Map

During the 1964 State Highway renumbering LRN 229 was reassigned as LRN 186 which is reflective on the State Highway Map of the same year.

1964 State Highway Map

According to CAhighways.org the path of LRN 186 was authorized to be built as part of the Interstate system in 1968. By 1969 the route of I-380 was defined by the Legislature and it's implied path appears on the 1970 State Highway Map .

1970 State Highway Map

I-380 is shown as mostly complete between US 101 and I-280 on the 1975 State Highway Map. There appears to be a small gap over the rails between CA 82 (former US 101) and US 101 on the Bayshore Freeway (former US 101 Bypass).

1975 State Highway Map

On the 1977 State Highway Map I-380 is shown fully completed between I-280 and US 101.

1977 State Highway Map

The extension of I-380 west to CA 1 in Pacifica would be cancelled by 1979 according to CAhighways.org.

CAhighways.org on Interstate 380

Interestingly I-380 has been the subject of several proposals for a new bridge across San Francisco Bay with the latest popping up in 2017. Most of the modern proposals would have the new crossing connecting with I-238 which would in theory remove the Interstate numbering violation. CAhighways.org summaries the I-380 extension proposals on the above link.

My approach to I-380 was from US 101 northbound at San Francisco International Airport.

As I approached the westbound ramp for I-380 there was a small but strong storm overhead. While my photos didn't turn out all that great given the strong rains I was able to get some "acceptable" enough samples to convey the route. As I-380 ascends over US 101 it enters the City of San Bruno.

I-380 westbound meets CA 82 approximately in the middle of it's routing. CA 82 is the historic route of the El Camino Real and original alignment of US 101 before the Bayshore Freeway was built.

I-380 westbound terminates at I-280. Traffic is given the option of heading both northbound and southbound on I-280.

Abandoned US Route 40 in the Truckee River Canyon

Within the Truckee River Canyon in the Sierra Nevada range numerous abandoned portions of US Route 40 can be found alongside modern Interstate 80. This segment of highway was opened during 1926 as a bypass of the Dog Valley Grade which carried the early North Lincoln Highway and Victory Highway. The corridor of the Truckee River Canyon State Highway would be assigned as US Route 40 when the US Route System was commissioned during November 1926. During 1958 the segment of Interstate 80 between Boca, California and the Nevada state line was complete. When Interstate 80 opened east of Boca numerous obsolete portions of US Route 40 were abandoned. Some of these abandoned segments have been incorporated into the Tahoe-Pyramid Trail. Part 1; the history of US Route 40 in the Truckee River Canyon The Truckee River Canyon for centuries has been an established corridor of travel known to native tribes crossing the Sierra Nevada range. The first documented wagon crossi...

Former US Route 50 and the Pioneer Route Lincoln Highway on Johnson's Pass Road

Johnson's Pass Road is one of the oldest highway corridors in California. Johnson's Pass was part of the Lake Tahoe Wagon Road as it was completed during 1856 over the Sierra Nevada. The pass would later be incorporated into the Pioneer Branch of the Lincoln Highway in 1913 and US Route 50 in 1926. Johnson's Pass Road would be bypassed by a new alignment of US Route 50 over Echo Summit in 1938. A replacement of the Meyers Grade east of Johnson's Pass would be opened to traffic in 1947. Johnson's Pass Road remains accessible to traffic and is still signed by the Lincoln Highway Association. Pictured as the blog cover is the view from the top of Johnson's Pass Road overlooking modern US Route 50 and Lake Tahoe. Part 1; the history of Johnson's Pass Much of the history of what become the Lake Tahoe Wagon Road is discussed in the September 1950 California Highways & Public Works during its Centennial Edition. The or...

Former California State Route 41 past Bates Station

When California State Route 41 was commissioned during August 1934 it was aligned along the then existing Fresno-Yosemite Road north of the San Joaquin River. Within the Sierra Nevada foothills of Madera County, the original highway alignment ran past Bates Station via what is now Madera County Road 209, part of eastern Road 406 and Road 207. Bates Station was a stage station plotted during the early 1880s at what was the intersection of the Coarsegold Road and Stockton-Los Angeles Road. The modern alignment bypassing Bates Station to the east would be reopened to traffic during late 1939. Part 1; the history of California State Route 41 past Bates Station Bates Station was featured as one of the many 1875-1899 Madera County era towns in the May 21, 1968, Madera Tribune . Post Office Service at Bates Station is noted to have been established on November 23, 1883 and ran continuously until October 31, 1903. The postal name was sourced...

Unknown said…

The next time you are in the area, you might want to approach I-380 from southbound 280. As you follow that ramp you will see an "overpass to nowhere" which apparently was meant to be the first piece of the planned westward extension over the hills to Pacifica.

2:43 PM

Jonathan - Beaver State Roads said…

I noticed that the exits on I-380 are numbered 5 for CA-82, but then 5A and 5B for I-280. Do you have any idea for the numbering discrepancy? Shouldn't the CA-82 exit have been numbered 5C, or I-280 4A and 4B?

4:14 AM