I lived in the heart of Sonoma Valley in the town of Glen Ellen for a year. What a great experience! My little cottage was on Arnold Dr. at the base of Sonoma Mountain, intersected by London Ranch Rd. where the Jack London State Park is located. This is where Jack London, author of Call of the Wild and Valley of the Moon ( another community of Sonoma Valley ), lived on his working ranch with his wife, Charmaine. When he and his wife died, the ranch was a gift to the State of California and today is a California State Park and Museum.
While wondering around the park you'll see a vineyard. These grapes are use in Kenwood Winery's, "London Ranch" label wine.
Driving up to Jack London State Park, you'll pass Benziger Winery. This is the original Glen Ellen Winery of which the town is named after. This is a fun winery with chickens running around, beautiful peacocks, and a friendly big dog to welcome you. Don't forget to take the tractor tour. If you're there in the summer and get hungry, stop at the Glen Ellen Market for their outdoor bar-b-que! Do make a point of going to B.R. Cohn Winery. Great wine, olive oils, and vinegars. The tasting room is like none other. B.R.Cohen was the manager to the Doobie Brothers and all the walls are lined with gold records and celebrity photos.
You can't go to Sonoma Valley without visiting the Plaza. When driving up Broadway St., you'll run right into it. This is where the California State Flag was born. There are many cute shops and restaurants that line the Plaza. The Plaza is the epicenter for many outdoor activities like farmers markets and food and art festivals.I love Sebastiani and Ravenswood Winery located just off the Plaza.
Want to spent the night? Right next to the Fairmont Mission Inn is a small, bright 11 room Inn called, Sonoma Creek Inn. I stayed before moving there and just love it! You can't beat the value!!
Traveling from San Francisco the best way to get to Sonoma Valley is to take the Bay Bridge / I80 East to Jameson Canyon ( to Napa ) to HWY 12 ( to Sonoma ). The 12 will join with HWY 121 ( now 12 / 121 ) to 12 / Broadway st. You will now be in the center of Sonoma Valley / Plaza. Follow the signs through town ( Napa St. )on HWY 12 which turns into the Sonoma Hwy / 12.
If you want to go to the Napa Valley from Sonoma , take the less traveled, local's road, Trinity Rd. Once on Trinity Road turn on to Dry Creek Rd. to Oakville Rd.. Oakville Rd. drops you right in to Rutherford, in the heart of Napa Valley. Do NOT drive this road at night if you're not familiar with it!
Otherwise, going back to San Francisco, take the HWY 116 to Petaluma, through country farmland to
HWY 1 south, right over the Golden Gate Bridge!
***Whatever you do, stay off HWY 101!!!*** Traffic is not fun and this road can be frustrating! Take it from someone who lived there!
I hope you enjoy Sonoma Valley as much as I did! I hope my information is helpful!