One such display is impressive. Five are wearisome. Ten are enough to drive you to drink.
But if Napa is a destination for oenophiles first and architecture buffs second a visitor can still map a stimulating tour focused on the buildings rather than the grapes.
The secret: Plan things in advance. Don't be distracted by every puffed-up bit of excess that looks good from the road, and don't look for subtle exercises in minimalism. Instead, remember that winery architecture serves two functions: to facilitate production and to put on a show.
"Wineries reflect different philosophies," says Gilles de Chambure, director of wine education for Meadowood resort in St. Helena. "You're telling a story about your connection to the land, and about your ambition: Do you want to announce that you've arrived, or do you want to look as if you've been there forever?"
Architecturally, the best winery buildings get their story straight. They set a distinctive tone and follow through with craft and conviction. They're built to endure - not just structurally, but by evoking some timeless sense of place.
So consider the list inside an opinionated taster's choice of wineries from Carneros to Calistoga that are worth a visit from an architectural perspective. They may not be masterpieces - some make the critic in me cringe - but at least they aren't cloying or cliched.
The Napa winery of modern vintage that casts the deepest spell is Robert Mondavi Winery on Highway 29 in Oakville. Even after 40 years it remains alluring - an unashamed homage to some mythical Spanish Mission past, complete with a bell tower, but done with such elegance that the result is a genuine landmark on its own.
The architect was Cliff May, arguably the state's best residential architect of the 20th century; here, he managed to strike a balance between modernism and make-believe. The tactile quality of the buildings is as otherworldly as anything in Santa Barbara or Santa Fe, including the textured stucco and low-slung wooden eaves - but the smooth leap of the building over the central gathering space couldn't occur without 20th century engineering smarts.
Another reason for the winery's success is the way that it sits so comfortably on the land. The tower has real presence from Highway 29; the drive in suggests you are approaching a genteel estate. And the low-key landscaping around the building is the ideal grace note.
Restraint has its virtues.
The best work of contemporary architecture in Napa is off-limits to the public: Dominus Estate in Yountville, an austere box that tucks all the winery operations behind walls formed by wire cages filled with basalt rocks. It's by Swiss architects Jacques Herzog and Pierre de Meuron, who later designed San Francisco's M.H. de Young Memorial Museum and were the 2001 recipients of the Pritzker Architecture Prize, the field's highest honor.
If you want a peek, turn west off Highway 29 onto Madison Street, take a sharp right and you're outside the estate - looking through its elegant screened metal fence. What you'll see is underwhelming, a long gray rectangle that projects no image at all.
It's a container made of containers.
The feeling that unfolds inside is something else, a hypnotic exercise in efficient restraint and low-key contradictions. The structure is heavy as can be, yet light and air seep in from outside. And while there's nothing organic about the shape, it has an earthiness that feels far more natural than the opulently landscaped showplaces elsewhere in the valley.
Another starchitect who left his mark - in a more accessible venue - is Michael Graves, a pioneer of postmodernism before achieving popular renown as Target's design guru. Unfortunately, his Clos Pegase on Dunaweal Lane in Calistoga isn't one of his better buildings; he won a competition for the project in 1984 with a design his statement claimed would "evoke memories of a European ancestry." In real life, the winery tries to be ironic and awe-inspiring at once, a pompous spoof of classicism that includes a single enormous column at the entry.
That said, stop by. The sculpture collection, with work by Henry Moore and Richard Serra, is dazzling. The procession of well-framed views and spaces show the ingenious care you expect from a serious architect - although the faded stucco could use freshening up.
Napa is also home to the only building in the United States by Friedensreich Hundertwasser, an Austrian artist who abhorred straight lines, subdued hues and conventionality of any sort. Turn off the Silverado Trail in the Stags Leap District, and you'll know when you've reached Quixote Winery - it's the low building engulfed by a tree-covered roof, with walls of bright meandering tiles and a gold dome that rises from a brick-accented roofline that slips and slides from north to south.
The quirkiest touch of all in Napa: The landscaping consists mainly of native bunchgrasses. There's hardly a grapevine in sight.
On the horizon by 2010 is the biggest name of all. Hall Wines is building a visitor's center for its winery just north of St. Helena that was designed by Frank Gehry - Pritzker Prize-winner, Bilbao Guggenheim creator and the only architect to be the featured guest on an episode of "The Simpsons." The center off Highway 29 will drape a flowing trellis over Gehry's signature billows and turns.
Not every building in Napa Valley pretends it was imported from another century, thank goodness. Several prominent newer wineries have modern abstract lines - and instead of rising triumphantly from vineyards, they burrow into hillsides or recline behind berms. Even so, they're still out to dazzle you with lavish airs. An early example is Domaine Chandon, which has a genuine presence (when it isn't thronged by the stretch-limo crowd). Great architecture? No. But better than most of its rivals, and the stripped-down forms and rhythmic scalloped roofline make up for the marketing frills inside the visitors' center.
Opus One, the palatial outpost on Highway 29, was built in 1991 by the Rothschild and Mondavi families to a design by Johnson Fain Partners of Los Angeles.
It is designed, emphatically, to make a statement: Approach the front door and you're engulfed by creamy limestone in a colonnaded plaza. The plaza, meanwhile, is cradled by grassy wings that slide up from out of the earth. Inside there's a spiral stone stairway leading down to the cellars, a salon off the left filled with antiques and more carved stone than you'll find in Venice.
The architectural guide available at the door uses the phrase "subtlety and grace" to describe the architecture. Hardly. But at least it doesn't skimp.
Ultimately, the architecture best suited to this hot western terrain is stripped down and lean: agricultural buildings with simple lines and durable wood, the type of structures that once rose as part of the workaday process of operating a ranch or an orchard.
You can still find the real thing, and a cluster of them can create a modest yet memorable sense of place. For proof, visit PlumpJack Winery on Oakville Cross Road. I'm no fan of the "whimsical" statuary or the San Francisco Marina vibe, but ignore all that. It's a dusty quadrangle of wood and stucco structures built between 1880 and the 1930s, shaded by mature oaks - rustic California at its weathered best.
The look was updated during the 1970s by Bay Area architect William Turnbull, one of the architects who had a hand in crafting the Sea Ranch on the Sonoma coast. The best example of his work is at Cakebread Cellars, which still has a Sea Ranch feel despite non-Turnbull extensions over the years. You see clean forms and modern lines that draw on the past without trying hard.
These days, the barnyard look is in vogue with smaller producers who want to project an anti-spectacle image. That can translate to mockitecture of a different sort - board-and-batten ensembles that aim for a tone of rustic ease, albeit at $85 or more a bottle. Rather than update the look using classic materials, a la Turnbull, these are designed to make you wonder if they're old or new.
Sometimes the result feels coy. But one winery where it works is Frog's Leap, where a simple red barn from 1884 off Conn Creek Road in Rutherford has evolved into a snug compound with the restored structure flanked by a respectful imitation and a visitors' center designed to look like a modest Victorian residence.
The buildings by Sonoma architect Ned Forrest are appropriately restrained, and arranged in a way that suggets the grounds evolved naturally. There's also an emphasis on environmental sustainability that goes beyond the half-acre of photovoltaic panels. The visitors' center includes woodwork made from reclaimed pickle vats. The structural beams had a prior life in a piano factory.
Also worth a visit (if only for novelty's sake) is Nickel & Nickel on Highway 29 in St. Helena. The grounds include a restored farmhouse, a barnlike structure where the wine ages - and a 200-year-old barn from New Hampshire. When its owners learned the barn with its red hemlock planks and white pine beams was targeted for demolition, they purchased the structure sight unseen, then had it dismantled and shipped to St. Helena. It was reassembled and turned into the winery's lab, with seismic reinforcements tucked discreetly inside.
It's a short step from the sublime to the ridiculous - and outside of Las Vegas, it's hard to imagine a landscape where so many buildings try so hard to make you think you're somewhere else.
This isn't a new trend in Napa - Jay Corley's replica of Thomas Jefferson's Monticello opened in 1984, five years before Domaine Carneros unveiled its lavish knockoff of an 18th century chateau - but every few years a freshly preposterous standard is set.
The latest structural spectacle shows this with eye-popping detail - so much so that it deserves a visit if only to gawk. I'm referring to Castello di Amorosa: Vintner Darryl Sattui's 107-room, 121,000-square-foot would-be medieval castle that comes with five tower-like battlements, one of which looks like it endured an artillery barrage.
When naysayers compare it to Disneyland, they're missing the point. Imitation was never so sincere, from the 200-year-old bricks made for the Hapsburg dynasty in Europe to the 2,000 custom Italian nails that anchor the oak doors of the immense "great hall." As for the stone along the wall, it's held in place by a mix of lime and sand and water, since cement didn't exist in the Middle Ages.
I can't vouch for the $25 guided tour ($30 on weekends) but the $10 tasting fee is worth it to wander the masonry-clad corridors and descend to a chambered vault where the wines are served - complete with Gregorian chants in the background.
"I love medieval architecture," Sattui says in an obvious understatement. "We tried to do an authentic job. My only compromise is that the floors are concrete. They should be chiseled stone."
By comparison, Darioush Khaledi's eponymous winery on the Silverado Trail seems almost demure. It has layers of Persian-themed opulence, such as the 16 freestanding stone columns topped by two-headed steeds. But little details like window mullions and interior walls are straightforward. Ho hum.
Who knows? Maybe the next time a castle or Tuscan villa sprouts in Napa Valley, it will be the real thing - imported from abroad.