Jump to content

California State Route 237

Route map:
From Wikipedia, the free encyclopedia

State Route 237 marker

State Route 237

Southbay Freeway
SR 237 highlighted in red
Route information
Maintained by Caltrans
Length11 mi[1] (18 km)
Existed1934–June 30, 1964 (as SR 9)
1964 renumbering–present
Major junctions
West end SR 82 in Mountain View
Major intersections SR 85 in Mountain View
US 101 in Sunnyvale
I-880 in Milpitas
East end I-680 in Milpitas
CountryUnited States
CountiesSanta Clara
Highway system
SR 236 I-238

State Route 237 (SR 237) is a state highway in the U.S. state of California that runs from El Camino Real (SR 82) in Mountain View to Interstate 680 in Milpitas. Known as the Southbay Freeway for most of its length, SR 237 runs south of the San Francisco Bay, connecting the East Bay to the Peninsula.

Route description[edit]

An aerial view of California State Route 237, Sunnyvale, looking east, taken from above a parking garage on the north side of the road
California State Route 237, San Jose, looking east from above Santa Clara

Route 237 begins at a junction of Grant Road with El Camino Real (SR 82) in Mountain View, as a four lane divided highway. Most traffic comes from California State Route 85. Westbound traffic can connect to Route 85 southbound, but the eastbound traffic connection to Route 85 northbound is labeled as an exit for U.S. 101. Route 237 intersects with Highway 101 at the southern corner of Moffett Field. After this intersection, a carpool lane is added, for a total of three lanes in either direction. It remains like this until the east end of the freeway at Interstate 880, where most eastbound traffic is directed to northbound I-880. The route then becomes a city street (an arterial road), Calaveras Boulevard, in Milpitas, terminating at Interstate 680.

Starting from half a mile after the highway's western terminus, and ending at the I-880 intersection, Route 237 is named the Southbay Freeway. It is mostly constructed to Interstate standards, although there are no current plans to make it an Interstate highway.

Route 237 is known for a number of companies that define Silicon Valley's technological landscape. Many major software and hardware manufacturers have their headquarters along 237. Some of these manufacturers include Lockheed-Martin, Brocade Communications Systems, Nortel Networks, Cisco Systems, Yahoo!, Juniper Networks, TiVo, Ariba and NetApp.

SR 237 is part of the California Freeway and Expressway System,[2] and is part of the National Highway System,[3] a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration.[4]

Highway 237 Bikeway[edit]

The Highway 237 Bikeway is a 5-mile (8.0 km) pedestrian and bicycle path that parallels State Route 237. The majority of the path is separated from vehicular traffic, however, two sections comprising a total of 1.5 miles (2.4 km) follow an on-street alignment adjacent the freeway.

This bikeway serves as an important connector in the network of trails in San Jose and Santa Clara County. It intersects with the Guadalupe River Trail, which provides access to Downtown San Jose, as well as the San Tomas Aquino Creek and Coyote Creek trails.[5]

Express lanes[edit]

The SR 237 Express Lanes, the 5-mile-long (8.0 km) high-occupancy toll (HOT) lanes along Route 237 in both directions between Mathilda Avenue in Sunnyvale and I-880 in Milpitas, opened on March 20, 2012, east of North First Street and on November 22, 2019, up to Mathilda Avenue.[6] Instead of terminating exactly at the I-880 interchange, the Express Lanes continue along an connector ramp to I-880, so that eastbound Express Lane users merge directly into the I-880 northbound HOV lane (which itself becomes an Express Lane), and I-880 southbound Express Lane users can directly enter Route 237's westbound Express Lane.

As of August 2020, the HOT lanes' hours of operation is weekdays between 5:00 am and 8:00 pm. Solo drivers are tolled using a congestion pricing system based on the real-time levels of traffic. Two-person carpools and clean air vehicles with a solo driver are charged 50 percent of the posted toll. Carpools with 3 or more people and motorcycles are not charged.[7] All tolls are collected using an open road tolling system, and therefore there are no toll booths to receive cash. Each vehicle is required to carry either a FasTrak Flex or CAV (Clean Air Vehicle) transponder, with its switch set to indicate the number of the vehicle's occupants (1, 2, or 3 or more). Solo drivers may also use the FasTrak standard tag without the switch.[7] Drivers without any FasTrak tag will be assessed a toll violation regardless of whether they qualified for free.[8]


Before Route 237 was upgraded to freeway status in 1994–1995, it was a four-lane expressway with at-grade intersections, known as Alviso-Milpitas Road or Milpitas-Alviso Road depending on different maps showing the description.

The Route 237 corridor has long been sought as a location for a freeway connector between Interstates 680 and 880. Many possible sites have been suggested, from Montague Expressway in North San Jose to Mission Boulevard in Fremont. One map printed before Route 237's construction to freeway standards between Alviso and 880 showed a new freeway across bay wetlands between Alviso and the Scott Creek Road interchange in South Fremont. Grading and underpasses for a freeway interchange are presently visible along 680 near Scott Creek Road. [1]

Major intersections[edit]

Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, based on the alignment that existed at the time, and do not necessarily reflect current mileage. R reflects a realignment in the route since then, M indicates a second realignment, L refers to an overlap due to a correction or change, and T indicates postmiles classified as temporary (for a full list of prefixes, see California postmile § Official postmile definitions).[9] Segments that remain unconstructed or have been relinquished to local control may be omitted. The entire route is in Santa Clara County.

Mountain ViewR0.00Grant RoadContinuation beyond SR 82
R0.001A SR 82 (El Camino Real) – Mountain View, Los AltosWest end of SR 237
West end of freeway

SR 85 north to US 101 north – San Francisco
Eastbound exit and westbound entrance; SR 85 south exit 22A

SR 85 south to SR 82 south – Los Gatos, Santa Cruz
Westbound exit and eastbound entrance; SR 85 north exit 22C
R0.611BDana StreetSigned as exit 1C westbound
M1.552Middlefield Road, Maude Avenue
US 101 south (Bayshore Freeway) – San Jose
Eastbound exit and westbound entrance US 101 north exit 396C
US 101 north (Bayshore Freeway) – San Francisco
Westbound exit and eastbound entrance; US 101 south exit 396B
Mathilda Avenue to US 101 – San Francisco, Sunnyvale
Former SR 9 south
SR 237 Express LanesWest end of Express Lanes
R3.974Fair Oaks AvenueEastbound exit and westbound entrance
R4.605Lawrence Expressway (CR G2), Caribbean Drive
Santa ClaraR5.836Great America Parkway
San Jose6.877North First Street
8.028Zanker Road
SR 237 Express LanesLast access point on mainline SR 237

I-880 north – Oakland
Express Lanes access only; eastbound exit and westbound entrance
MilpitasR9.139AMcCarthy Boulevard
9.349 I-880 (Nimitz Freeway) – Oakland, San JoseSigned as exits 9B (south) and 9C (north); I-880 north exit 8B, south exit 8B-C; former SR 17
East end of freeway
10.0010Main StreetInterchange; exit ramps to Main Street from both directions; former SR 238
11.0811 I-680 – Sacramento, San JoseInterchange; signed as exits 11A (south) and 11B (north); east end of SR 237; I-680 exit 8
11.08Calaveras BoulevardContinuation beyond I-680
1.000 mi = 1.609 km; 1.000 km = 0.621 mi

See also[edit]


  1. ^ a b California Department of Transportation (July 2007). "Log of Bridges on State Highways". Sacramento: California Department of Transportation.
  2. ^ "Article 2 of Chapter 2 of Division 1". California Streets and Highways Code. Sacramento: California Office of Legislative Counsel. Retrieved February 6, 2019.
  3. ^ Federal Highway Administration (March 25, 2015). National Highway System: San Francisco–Oakland, CA (PDF) (Map). Scale not given. Washington, DC: Federal Highway Administration. Retrieved September 5, 2017.
  4. ^ Natzke, Stefan; Neathery, Mike & Adderly, Kevin (June 20, 2012). "What is the National Highway System?". National Highway System. Washington, DC: Federal Highway Administration. Retrieved July 1, 2012.
  5. ^ "Highway 237 Bikeway". San Jose Trail Network Website. City of San Jose. Retrieved 2008-03-31.
  6. ^ "VTA opens Highway 237 express toll lanes". KTVU-TV. March 20, 2012. Archived from the original on November 27, 2012. Retrieved March 31, 2012.
  7. ^ a b "SR-237 Express Lanes". www.bayareafastrak.org. CalTrans. Retrieved August 14, 2022.
  8. ^ "Pay Tolls & Violations". www.bayareafastrak.org. CalTrans. Retrieved August 14, 2022. If you use Bay Area Express Lanes, you must use a FasTrak toll tag, otherwise you will receive a violation notice including toll evasion penalties
  9. ^ a b California Department of Transportation. "State Truck Route List". Sacramento: California Department of Transportation. Archived from the original (XLS file) on September 5, 2015. Retrieved June 30, 2015.
  10. ^ California Department of Transportation, All Traffic Volumes on CSHS, 2005 and 2006
  11. ^ California Department of Transportation, California Numbered Exit Uniform System, SR-237 Eastbound and SR-237 Westbound, accessed February 2008

External links[edit]

KML is from Wikidata