From there the Russian River flows south, past Ukiah and Hopland, and crosses into Sonoma County just north of Cloverdale. It flows south past Cloverdale, Asti, and Geyserville. 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. In that area, State Route 116 parallels the river, bordering it past Guernewood Park and Monte Rio.East of Healdsburg, Maacama Creek joins the Russian River. Austin Creek enters from the north before the River passes through Duncans Mills.It is very safe at that time for swimming and boating, with a gentle current. Holway wrote of the Russian River in his paper "The Russian River: A Characteristic Stream of the California Coast Ranges".
However, in 2007, the Sonoma County Water Agency completed a comprehensive re-evaluation of historical records, coupled with a 5-year monitoring program using underwater cameras at two fish ladders just north of Forestville.
They found that Chinook always were, and still are, "a relatively abundant, widely distributed, and naturally self-sustaining population".
The earliest European name for the river, Slavyanka, appears on a Russian-American Company chart dated 1817.
The river takes its current name from Russian Ivan Kuskov of the Russian-American Company, who explored the river in the early 19th century and established the Fort Ross colony 10 mi (16 km) northwest of its mouth.
The mouth is about 60 mi (100 km) north of the San Francisco Bay's Golden Gate bridge.