I have observed a lot of postings on Stanford and Palo Alto lately and rightly so I might add - lovely area. One of my favorite things to do when in Northern California is visit Napa Valley although I have been told Sonoma is great as well. Someone mentioned that Sonoma may be more on the white wine side whereas Napa is possibly slanted more toward reds
Anyhoo... here are some of my Napa favorites and would love to hear what some of yours are...
Silver Oak - lovely winery and fabulous wine. Silky smooth cabs and merlots. Here in Cleveland the wine is about $150 a bottle in restaurants. Can buy it for about half that much at the winery. We always take their taste testing tour. Once there was a small crowd and they just kept pouring for us for over an hour. You cannot imagine how good we felt when we left that day
Viader - just tried some of this recently in Seattle and it is one of the best tasting wines I have ever had. It is a blended wine and excellent quality. My friends recently visited the winery and they enjoyed it.
ZD Winery - Excellent quality reds and whites. Lovely winery. A friend of mine loves their Chardonay.
Coppola-Neibaum - I believe the name may have changed but that is Coppola as in Francis Ford. We always stop here for the beauty of the winery. It will put you in a good mood just visiting this place. Lovely fountains and architecture. The wine is average imho but that never detours us from stopping. On the second floor, many of Coppola's academy awards and movie momentos are on display which is cool.
Caymus - this is by appointment only. Again their wines were ok but the personalized taste testing and historical perspective offered was nice. Lovely winery and I believe this entity is formed from a conglomerate of wine makers.