Editing Sonoma County, California (section)

===Major highways===
[[File:US 101 (1961 cutout).svg|25px|link= |alt=]] [[U.S. Route 101 in California|U.S. Route 101]]

U.S. Route 101 is the westernmost [[United States Numbered Highways|Federal highway]] in the U.S.A. Running north/south through the states of California, [[Oregon]], and Washington, it generally parallels the coastline from Downtown Los Angeles to the [[Canada–United States border|Canada–US border]]. Highway 101 links seven of the county's nine incorporated cities: Cloverdale, Healdsburg, Windsor, Santa Rosa, Rohnert Park, Cotati, and Petaluma. It is a freeway for its entire length within the county.

The four-lane sections of the highway have been heavily congested during peak commute hours for many years and work is being done to widen part of the highway to six lanes. The segment from north of Petaluma (at Old Redwood Highway/Petaluma Boulevard North exit) to Windsor has been fully widened, as has the segment from the Petaluma River bridge to the Marin County border. The two new inner lanes are designated for [[High-occupancy vehicle|vehicles with two or more occupants]] during commute hours. Work is being done around Petaluma to finish the widening within Sonoma County; the widening also involves upgrading the highway to [[Interstate Highway standards|full freeway standards]].

[[File:California 1.svg|20px|link= |alt=]] [[California State Route 1|State Route 1]]

Within Sonoma County, Highway 1 follows the coastline from the Mendocino County border, at the mouth of the Gualala River, to the Marin County border, at the Estero Americano ([[Americano Creek]]), southeast of Bodega Bay.

[[File:California 12.svg|20px|link= |alt=]] [[California State Route 12|State Route 12]]
[[File:CA SR-12 Sonoma.jpg|thumb|right|[[California State Route 12|State Route 12]] in Sonoma (Broadway)]]

Highway 12 runs eastward from its intersection with Highway 116 in Sebastopol to Santa Rosa. There it turns south through the Valley of the Moon to Sonoma, then east into Napa County. The four-lane freeway section within Santa Rosa, between Fulton Road and Farmers Lane, is called the Luther Burbank Memorial Highway. That section, especially where it crosses Highway 101, is severely congested during peak commute hours.

The two-lane Bodega Highway runs west from the intersection of Highways 12 and 116 in Sebastopol, through the coastal hills to its intersection with Highway 1, east of Bodega Bay. East of Santa Rosa, Highway 12 is also called Sonoma Highway; and east of the City of Sonoma, Carneros Highway.

[[File:California 37.svg|20px|link= |alt=]] [[California State Route 37|State Route 37]]

Highway 37 connects Highway 101 at Novato, in Marin County, with Interstate 80 in Vallejo, in Solano County, at the top of San Pablo Bay. Within Sonoma County, it is also called Sears Point Road.

[[File:California 116.svg|25px|link= |alt=]] [[California State Route 116|State Route 116]]

Highway 116 is a winding, two-lane rural route that runs from Jenner, at the mouth of the Russian River on the coast, southeast to Arnold Drive near Sonoma. It is also called "Pocket Canyon" between Guerneville and Forestville; Gravenstein Highway North, between Forestville and Sebastopol; and Gravenstein Highway South, between Sebastopol and Stony Point Road, west of Rohnert Park. East of Petaluma it is called Lakeville Highway, then Stage Gulch Road.

[[File:California 121.svg|25px|link= |alt=]] [[California State Route 121|State Route 121]]

Highway 121 is a two-lane rural route running from Highway 37 near Sears Point Raceway to Highway 128 in [[Lake Berryessa]], in Napa County.

[[File:California 128.svg|25px|link= |alt=]] [[California State Route 128|State Route 128]]

The northernmost section of Highway 128 is a two-lane, rural route running southeast from Highway 101 at Geyserville, north of Healdsburg, through the Alexander Valley and into Napa County.