Santa Rosa is on US Highway 101, an hour by car north of San Francisco when the traffic moves and two hours when it doesn't. The drive from San Francisco crosses the Golden Gate Bridge and runs up through Marin County; from Sacramento it is about two hours west across the wine country.
Charles M. Schulz–Sonoma County Airport (STS) is fifteen minutes from downtown and has direct flights to Los Angeles, Seattle, Denver, Portland, Las Vegas, and Phoenix. For more options most travellers use San Francisco (SFO) or Oakland (OAK).
The SMART commuter train runs from Larkspur Landing (with a ferry connection to San Francisco) north through Santa Rosa to Cloverdale. It is the most relaxing way to arrive from the south. There is also a Golden Gate Transit bus from the city centre of San Francisco that takes about two hours.