California State Route 120
|Maintained by Caltrans|
|Length||152.562 mi (245.525 km)|
(Does not include the portion in Yosemite)
|Restrictions||Segment through Tioga Pass closed in winter|
|West end||I-5 in Lathrop|
|East end||US 6 at Benton|
|Counties||San Joaquin, Stanislaus, Tuolumne, Mono|
State Route 120 (SR 120) is a state highway in the U.S. state of California, running west to east across the central part of the state. It runs from Interstate 5 in Lathrop in the San Joaquin Valley through Yosemite National Park, to its end at U.S. Route 6 in Mono County, in eastern California. While the route is signed as a contiguous route through Yosemite National Park, the portion in park boundaries is federally maintained, and is not included in the state route logs. The portion at Tioga Pass is the highest paved through road in the California State Route system. This part is not maintained in the winter and is usually closed during the winter season.
SR 120 begins as a freeway intersecting Interstate 5 to extend Interstate 205 through Manteca. In east Manteca the freeway ends at SR 99 and becomes a highway which continues to head east through Escalon, Oakdale and other various small towns. East of Oakdale there are no highly populated areas for 90 miles (144 km) as it heads into the foothills of the Sierra Nevada and into Yosemite National Park. Entering Yosemite, SR 120 is known as Big Oak Flat Road as it heads towards Crane Flat. After leaving Crane Flat, Big Oak Flat Road turns southeast towards Yosemite Valley, while SR 120 continues east as Tioga Pass Road (or often simply Tioga Road). The highway retains that name as it travels through Tuolumne Meadows, over Tioga Pass at an elevation of 9,945 feet, and through the Lee Vining Canyon on its 59-mile (95 km) journey to its intersection with U.S. Route 395, at Lee Vining. After a jog to the south along US 395, it continues east as Mono Mills Road, skirting the south end of Mono Lake and providing access to the Mono Lake South Tufa as well as the historical site of Mono Mills before cresting Sagehen Summit and ending with the intersection of U.S. Route 6 at Benton. Both the portions through Yosemite National Park and the stretch south of Mono Lake are subject to winter closure. Usually the highway is open through Tioga Pass by the Memorial Day weekend at the end of May, and typically closes for the winter sometime in November.
Tioga Road/Big Oak Flat Road is officially both a National Scenic Byway and a National Forest Scenic Byway. The segment through the Lee Vining Canyon between the eastern edge of Yosemite and US 395 is designated as the Lee Vining Canyon Scenic Byway, a separate National Forest Scenic Byway.
SR 120 is part of the California Freeway and Expressway System, and both the western portion and the eastern portion west of US 395 are part of the National Highway System, a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration. SR 120 is eligible to be included in the State Scenic Highway System, but it is not officially designated as a scenic highway by the California Department of Transportation. The Tioga Pass Road was designated as a California Historic Civil Engineering Landmark by the American Society of Civil Engineers in 2002.
During the Gold Rush, SR 120 was originally known as Big Oak Flat Road, after the village of Big Oak Flat through which it passes in the Sierra foothills. It was a pack trail from Stockton which became popular with prospectors about 1849. By 1874 it was a wagon road which extended to Yosemite Valley.
In 1921, the California State Assembly authorized San Joaquin County to transfer the county road connecting Manteca with then-Route 5 (now I-5) at Mossdale to the state. It was numbered Route 66, as was a 1933 extension from Manteca east to Route 13 in Oakdale. Also in 1933, Route 40 was extended east from Mono Lake to Route 76 (US 6) at Benton. The route from Manteca to Benton was marked as Sign Route 120 in 1934, and was soon extended west to Mossdale, replacing what had been part of U.S. Route 99W.
West of Priest is a section of highway with over one hundred curves and hairpin turns, known as the "New Priest Grade." With a 4% grade, it opened in 1915 and was built by a group of local volunteers who desired an alternative to the very steep (17%) Old Priest Grade. Today, both grades are paved, but trailers and RVs are prohibited from Old Priest Grade. There is a 7,500-pound weight limit on the old grade.
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 ( ). Segments that remain unconstructed or have been relinquished to local control may be omitted. The numbers reset at county lines; the start and end postmiles in each county are given in the county column.
|Lathrop||R0.49||1||I-5 – San Francisco, Los Angeles, Stockton, Sacramento||Westbound exit and eastbound entrance; signed as exits 1A (south) and 1B (north); west end of SR 120; former US 50 west; I-5 exit 461|
|Manteca||R1.33||1C||Yosemite Avenue||Signed as exit 1 eastbound|
|R3.32||3||Airport Way (CR J3) – Sharpe Depot|
|R4.31||4||Union Road||Diverging diamond interchange, first one constructed in California and opened to traffic on November 25, 2020.|
|R5.31||5||South Main Street|
SR 99 south – Modesto, Fresno, Los Angeles
|West end of SR 99 overlap; SR 99 exit 241|
|||East end of freeway on SR 99|
SR 99 north / Yosemite Avenue – Central Manteca
|Interchange; east end of SR 99 overlap; SR 99 exit 242|
|8.84||CR J5 (Jack Tone Road)|
|||11.64||French Camp Road|
CR J6 / CR J7 north (Escalon-Bellota Road, McHenry Avenue) – Farmington, Modesto
|West end of CR J7 overlap|
CR J7 south (Main Street) / Kern Street
|East end of CR J7 overlap|
CR J9 north (Valley Home Road) – Valley Home
|West end of CR J9 overlap|
CR J14 north (Twenty-Six Mile Road)
|West end of CR J14 overlap|
SR 108 west (F Street) / CR J9 / CR J14 south (Yosemite Avenue) – Modesto
|West end of SR 108 overlap; east end of CR J9 / CR J14 overlap|
|||8.19||CR J59 (La Grange Road) – La Grange, Merced|
|||||CR E15 (O'Byrnes Ferry Road) – Copperopolis|
SR 108 east – Sonora
|East end of SR 108 overlap|
SR 49 north – Sonora
|West end of SR 49 overlap|
|Tuolumne River / Don Pedro Reservoir||R19.61||James E. Roberts Bridge|
SR 49 south – Coulterville, Mariposa
|East end of SR 49 overlap|
CR J132 (Smith Station Road, Greeley Hill Road) to SR 132 – Coulterville, Merced
|Yosemite National Park||East end of state maintenance at western park boundary|
|||Big Oak Flat Entrance Station; park fee or annual pass required for entry|
Big Oak Flat Road to SR 41 / SR 140 – Yosemite Valley
|Closed in winters east of here through Tioga Pass|
|||Tioga Pass Entrance Station; park fee or annual pass required for entry|
|||West end of state maintenance at eastern park boundary|
|||R8.54||Gate (closed in winters west of here through Tioga Pass)|
US 395 north / Airport Road – Reno
|West end of US 395 overlap|
|June Lake Loop North Junction||46.40[N 2]|
SR 158 south – June Lake
|Mono Mills Junction||45.96[N 2]|
US 395 south – Bishop
|East end of US 395 overlap|
|Benton||58.99||US 6 – Tonopah, Bishop||East end of SR 120|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi|
- California Department of Transportation. "State Truck Route List". Sacramento: California Department of Transportation. Archived from the original (XLS file) on June 30, 2015. Retrieved June 30, 2015.
- "The Tioga Road; a History 1883-1961 (1961, 1980), "Reconstruction," by Keith A. Trexler". yosemite.ca.us.
- "Floodgap Roadgap's Summer of 6 -- U.S. Highway 6, Part 1: US 6 in California (Bishop to Nevada State Line; Inyo County, Mono County)". floodgap.com.
- Staff. "Tioga Road/Big Oak Flat Road". America's Byways. Federal Highway Administration. Archived from the original on November 20, 2011. Retrieved November 29, 2011.
- Staff. "Lee Vining Canyon Scenic Byway". America's Byways. Federal Highway Administration. Archived from the original on October 23, 2011. Retrieved October 23, 2011.
- "Article 2 of Chapter 2 of Division 1". California Streets and Highways Code. Sacramento: California Office of Legislative Counsel. Retrieved February 6, 2019.
- Federal Highway Administration (March 25, 2015). National Highway System: California (North) (PDF) (Map). Scale not given. Washington, DC: Federal Highway Administration. Retrieved September 30, 2017.
- 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.
- "Article 2.5 of Chapter 2 of Division 1". California Streets & Highways Code. Sacramento: California Office of Legislative Counsel. Retrieved February 6, 2019.
- California Department of Transportation (August 2019). "Officially Designated State Scenic Highways and Historic Parkways" (XLSX). Sacramento: California Department of Transportation. Retrieved September 30, 2017.
- "The Tioga Pass Road Historical Marker". The Historical Marker Database. Retrieved March 6, 2021.
- Statutes 1921 p. 1627: State highway in San Joaquin County
- California Department of Transportation, State Highway Routes: Selected Information, 1994 with 1995 revisions
- Dennis, T.H. (August 1934). "State Routes Will Be Numbered and Marked with Distinctive Bear Signs". California Highways and Public Works. 11 (8): 20–21, 32. ISSN 0008-1159 – via Archive.org.
- H.M. Gousha Company, California Archived October 13, 2007, at the Wayback Machine, 1942
- American Association of State Highway Officials, log of U.S. Highways, American Highways, ca. 1932
- "BLM Granite Mountain Wilderness". Archived from the original on August 28, 2016. Retrieved August 27, 2016.
- "Priest Grade, Grizzly Gulch". Pine Mountain Lake Association. Archived from the original on October 4, 2013. Retrieved June 6, 2013.
- "CA-120 E". Google, Inc. Retrieved June 6, 2013.
- California Department of Transportation (July 2007). "Log of Bridges on State Highways". Sacramento: California Department of Transportation.
- California Department of Transportation, All Traffic Volumes on CSHS, 2005 and 2006
- California Department of Transportation, California Numbered Exit Uniform System, SR-120 Eastbound and SR-120 Westbound, accessed February 2008
- "Yosemite National Park Fees & Passes". National Park Service. Retrieved December 31, 2021.
- Map: "Stanislaus National Forest, California," U.S. Forest Service, 1979.