Back California State Route 99 German Ruta Estatal de California 99 Spanish California State Route 99 Dutch California State Route 99 SIMPLE 99号加利福尼亚州州道 Chinese California Chiu Kong-lō͘ 99 ZH-MIN-NAN
 State Route 99 | ||||
|---|---|---|---|---|
 SR 99 highlighted in red | ||||
| Route information | ||||
| Maintained by Caltrans | ||||
| Length | 424.85 mi[1] (683.73 km) | |||
| Existed | 1926 as US 99, 1964 as SR 99–present | |||
| Major junctions | ||||
| South end |  I-5 near Wheeler Ridge | |||
| North end |  SR 36 near Red Bluff | |||
| Location | ||||
| Country | United States | |||
| State | California | |||
| Counties | Kern, Tulare, Fresno, Madera, Merced, Stanislaus, San Joaquin, Sacramento, Sutter, Butte, Tehama | |||
| Highway system | ||||
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State Route 99 (SR 99) is a major north–south state highway in the U.S. state of California, stretching almost the entire length of the Central Valley. From its southern end at Interstate 5 (I-5) near Wheeler Ridge to its northern end at SR 36 near Red Bluff, SR 99 goes through the densely populated eastern parts of the valley. Cities served include Bakersfield, Delano, Tulare, Visalia, Fresno, Madera, Merced, Turlock, Modesto, Manteca, Stockton, Sacramento, Yuba City, and Chico.
The highway is a remnant of the former Mexico to Canada U.S. Route 99 (US 99), which was decommissioned in 1972 after being functionally replaced by I-5 for long-distance traffic. The entire segment from Wheeler Ridge to Sacramento has been upgraded as of January 2016 to a freeway at least four lanes wide, and the California Department of Transportation (Caltrans) plans to further upgrade the segment to a minimum width of six lanes and also bring it into compliance with Interstate Highway standards as a parallel route to I-5 for Los Angeles–Sacramento traffic. North of Sacramento, the road ranges from a rural two-lane road to a four-lane freeway, with much of it following the route formerly designated as US 99E.
A 2024 study conducted by a Dallas law firm looked at federal data over a five-year span between 2018 and 2022, concluding that SR 99 is the most dangerous highway in California, with 445 deaths (an average of 89 per year) over that five-year period.[2]
- ^ Cite error: The named reference
bridgelogwas invoked but never defined (see the help page). - ^ "California's Highway 99 is deadliest route in the state, study finds". CBS News Sacramento. June 24, 2024. Retrieved June 25, 2024.