The Russian River, a southward-flowing river, drains 1,485 square miles of Sonoma and Mendocino counties in Northern California. It is the second-largest river (after the Sacramento River) flowing through the nine-county Greater San Francisco Bay Area, with a mainstem 110 miles long.
The Russian River springs from the Laughlin Range about 5 miles east of Willits in Mendocino County. It flows generally southward to join the East Fork Russian River just below Lake Mendocino.
From there the Russian River flows south, past Ukiah and Hopland, and crosses into Sonoma County just north of Cloverdale. Closely paralleled by U.S. Route 101, it descends into the Alexander Valley. After it makes a series of sweeping bends, the river turns westward, where it is spanned by the Wohler Bridge, and it is joined by Mark West Creek north of Forestville, followed by Green Valley Creek to the south. The river passes Rio Nido and Guerneville. In that area, State Route 116 parallels the river, bordering it past Guernewood Park and Monte Rio.
Highway 1 crosses over the river before it flows into the Pacific Ocean between Jenner and Goat Rock Beach. The Russian River estuary is recognized for protection by the California Bays and Estuaries Policy. The mouth is about 60 miles north of the San Francisco Bay's Golden Gate bridge.
The lower Russian River is a popular spring, summer, and fall destination for navigation and recreation. It is very safe at that time for swimming and boating, with a gentle current. The river can be dangerous in the winter, with swift current and muddy water.
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