The Petaluma River is a tidal river located in Sonoma County, California. It flows approximately 55 miles from its source in the hills of the Sonoma Valley to its mouth at San Pablo Bay. The river is an important waterway for local wildlife and serves as a habitat for various species, including fish and birds. Historically, the Petaluma River was a vital transportation route for early settlers and farmers in the region. Today, it supports recreational activities such as kayaking and fishing, while also playing a role in local agriculture and flood management efforts.