California State Route 237

State Route 237
Southbay Freeway
Route information
Defined by Streets and Highways Code § 537
Maintained by Caltrans
Length:	11.00 mi[1] (17.70 km)
Major junctions
West end:	SR 82 in Mountain View
	SR 85 in Mountain View US 101 in Sunnyvale I-880 in Milpitas
East end:	I-680 in Milpitas
Highway system
State highways in California Interstate U.S. State Pre-1964 History Unconstructed Deleted Freeway Scenic ← SR 236 I-238 →

State Route 237 runs from El Camino Real (SR 82) in Mountain View to Interstate 680 in Milpitas. It runs south of the San Francisco Bay, connecting the East Bay to the Peninsula.

This route is part of the California Freeway and Expressway System.^[2]

Route description

Route 237 begins at a junction of Grant Road with El Camino Real (CA-82) in Mountain View, as a freeway with two lanes in each direction, although most traffic comes from State Route 85. Westbound traffic can connect to Highway 85 southbound, but the eastbound traffic connection to 85 northbound is labeled as an exit for U.S. 101. It intersects with Highway 101 at the southern corner of Moffett Field. After this intersection, a carpool lane is added, for a total of 3 lanes in either direction. It remains like this as until the east end of the freeway at Interstate 880, where most eastbound traffic is directed to northbound 880. The route becomes a street, Calaveras Boulevard, in Milpitas, terminating at Interstate 680.

Before Route 237 was upgraded to freeway status in the mid-1990s, it was a 4-6 lane street, known as Alviso-Milpitas Road or Milpitas-Alviso Road depending on different maps showing the description. Exit signs from U.S. 101 north to Route 237 west currently say "Mountain View-Alviso Road". Starting from half a mile after the highway's western terminus, and ending at the I-880 intersection, Route 237 is constructed to Interstate standards, and is named the Southbay Freeway. It is not part of the Interstate system, however.

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 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.

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.

Highway 237 Bikeway

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.^[3]

Express lanes

The SR 237 Express Lanes, the 4-mile-long (6.4 km) high-occupancy toll (HOT) lanes along Route 237 in both directions between North First Street in San Jose and I-880 in Milpitas, opened on March 20, 2012.^[4] Instead of terminating exactly at the I-880 interchange, the Express Lanes continue along the connector ramp to northbound I-880. Solo drivers are required to pay a toll via a FasTrak transponder. Later on, VTA will add express lanes to SR 85, US 101, and also extend the SR 237 Express Lanes to Mathilda Ave.

Major intersections

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 an overlap due to a correction or change, and T indicates postmiles classified as temporary (for a full list of prefixes, see the list of postmile definitions).^[5] Segments that remain unconstructed or have been relinquished to local control may be omitted. The entire route is in Santa Clara County.

Location	Postmile [5][6][7]	Exit [8]	Destinations	Notes
Mountain View	R0.00		Grant Road	Continuation beyond SR 82
	R0.00	1A	SR 82 (El Camino Real) – Mountain View, Los Altos	West end of SR 237
	​	West end of freeway
	R0.38	1A	To US 101 north (via SR 85 north) – San Francisco	Eastbound exit and westbound entrance; SR 85 south exit 22A
	R0.38	1B	SR 85 south to SR 82 south – Los Gatos, Santa Cruz	Westbound exit and eastbound entrance; SR 85 north exit 22C
	R0.61	1B	Dana Street, Evelyn Avenue, Whisman Road	Signed as exit 1C westbound
	M1.55	2	Middlefield Road, Maude Avenue
Sunnyvale	2.48	3A	US 101 south (Bayshore Freeway) – San Jose	Westbound exit is via exit 3B; US 101 north exit 396C, south via exit 396A
	2.48	3A	US 101 north (Bayshore Freeway) – San Francisco	Eastbound exit is via exit 3B; US 101 south exit 396B, north via exit 396A
	2.99	3B	Mathilda Avenue – Sunnyvale	Former SR 9 south
	R3.97	4	Fair Oaks Avenue	Eastbound exit and westbound entrance
	R4.60	5	Lawrence Expressway (CR G2), Caribbean Drive
Santa Clara	R5.83	6	Great America Parkway, Lafayette Street
San Jose	​	—	SR 237 Express Lanes west	End of westbound Express Lanes
	6.87	7	North First Street
	8.02	8	Zanker Road
	​	—	To I-880 north / SR 237 Express Lanes east – Oakland	Start of eastbound Express Lanes; last access point from main eastbound SR 237 lanes
Milpitas	R9.13	9A	McCarthy Boulevard
	9.34	9	I-880 (Nimitz Freeway) – Oakland, San Jose	Signed as exits 9B (south) and 9C (north); I-880 north exit 8B, south exit 8B-C
	​	East end of freeway
	10.00	10	Main Street	Interchange; westbound exit and eastbound entrance; former SR 238
	11.08	11	I-680 – Sacramento, San Jose	Interchange; signed as exits 11A (south) and 11B (north); east end of SR 237; I-680 exit 8
	11.08		Calaveras Boulevard	Continuation beyond I-680
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       ETC       Incomplete access

See also

• List of California State Routes

References

External links

Route map: Bing / Google

• Bay Area FasTrak – includes information on the SR 237 HOT lanes and other toll facilities in the San Francisco Bay Area
• Caltrans: Route 237 highway conditions
• California Highways: SR 237
• Highway 237 / I-880 Interchange Reconstruction Project