Ok boys and girls, the call of the question was:
What is your single (that means ONE) favorite California vineyard?
I’m going to synthesize the responses when I return from the 25th annual gathering of the clan, Ardbeggeddon XXV, later in the week (if I survive) and will choose the first vineyard mentioned by those who are hard of reading and mentioned more than one. That means that you can edit your response if you desire, while I am gently polishing my liver.
The question would be more meaningful if it was by major variety. Otherwise, the answer is distorted by the variety of wine one likes to drink.
Just to frustrate M. Kaplan. 
Favorite Oakville Vineyard
MacDonald
Favorite St Helena Vineyard
Dr. Crane
Favorite Rutherford Vineyard
Greer
Favorite Yountville Vineyard
Napanook
Favorite Oak Knoll Vineyard
Moulds
Favorite Coombsville Vineyard
Meteor
Favorite Calistoga Vineyard
Eisele
Favorite Howell Mtn Vineyard
Cimarossa
Favorite Spring Mtn Vineyard
Cain
Favorite Mt Veeder Vineyard
Sage
Favorite Oakville East Vineyard
Oakville Ranch
Favorite Pritchard Hill Vineyard
Bryant
Favorite Stags Leap Vineyard
Steltzner
Favorite Diamond Mtn Vineyard
Armstrong Ranch
Favorite Carneros Vineyard
Hudson
Favorite Westside Rd. Russian River Vineyard
Allen
Favorite Fort Ross Vineyard
McDougall Ranch
Favorite Freestone Vineyard
Occidental Cellars
Favorite Santa Rita Hills Vineyard
Fe Ciega
Favorite Santa Maria Vineyard
Bien Nacido Block Z
Umm, Roy, what’s your favorite Santa Cruz Mountain vineyard?
And while you’re at it, what’s your favorite Cucamonga vineyard?
Thank you.
Dan Kravitz
You misspelled Lagier Meredith
I love this vineyard so much I named one of my cats Rosella. Somewhat humorous story - I told this to Rosella Franscioni and she looked at me like I was nuts but her son seemed very pleased.
Shafer in Napa, Aston Estate in Sonoma (Thomas Rivers Brown owns it), Devils Gulch in Marin County, and shout out to Red Cap on Howell Mountain - small production beautiful Cabs.
You forgot Tench, Roy!
Dr Crane and JJ Cohn are tied for my favorites.
Martha’s
Yes, the answers may be distorted by the varieties of wines people like, but that is ok as it is a window into people’s wine preferences.
I posted the original question because I saw the video above about Evangelho, which is the source for my current favorite California wine, Hardy’s Mourvèdre, and has produced great wines for a very long time in an area that is not as highly esteemed as others.
Currently: Evangelho
It was Monte Rosso for a long time back when Ravenswood was making wine from there.
It might be recency bias from a stellar Bedrock Pagani last night and the sense memories it evoked had me thinking Pagani.
In the mix are Old Hill, Monte Rosso, and Lytton Springs.
Bates Ranch doesn’t make your list?
Bates Ranch is great, but Cabernet Sauvignon is not a grape where terroir and old vines meet together in the same way as these historic Zinfandel and mixed-blacks vineyards. The Pagani last night took me back to the 90s when I first encountered it.
Eisele. One of the most unique locations in Napa Valley.
I agree on Eisele but prices today are crazy. Had to stop buying the main bottling 3 years ago. Can find other wines of similar quality for much cheaper.
For sure. But if price were no object (and price is not mentioned in the OP) I would drink all of the Eisele sourced wines.
Definitely true! Just wanted to comment.
Tough question.
If it’s a “you’re stuck with this one vineyard for the rest of your life” question, I’d agree with Bien Nacido. IMO one of the most if not consistent every year, and like Larry said the multiple varieties.
If it’s like a last meal before execution and you get one vineyard before it’s lights out forever, maybe Martha’s.