Buena Vista is California's first premium winery, founded in 1857 by Count Agoston Haraszthy a mile northeast of the Plaza and now run under Jean-Charles Boisset. The grounds hold the 1862 Press House, hand-dug caves, a wine-tool museum, and a sparkling-focused Bubble Lounge — a half-day in themselves. The destination at the end of the walk.

Sonoma's Best is a wine bar and wine club a few blocks east of the Plaza, built around Master Sommelier Todd Jolly's list of world-renowned wines and top spirits under a full liquor license. A marketplace and deli round out the space, and four cottages offer an overnight retreat. Known for an easy, community-minded welcome.

Winery Sixteen 600 is the family label of Phil Coturri, the viticulturist behind much of Sonoma Valley's organic farming, working from a 120-year-old farmhouse a block off the Plaza. Tastings are seated and comparative — certified-organic Grenache, Zinfandel, and Cabernet poured from antique theater seats while records play. By appointment.

WALT, the Hall family's Pinot label, works a room off the northwest corner of the Plaza, pouring single-vineyard Pinot Noir and Chardonnay from across the Pacific Coast — Sonoma Coast to Anderson Valley to Oregon. The signature flight runs the length of it, what the room calls a thousand miles of Pinot. Caviar and charcuterie on the side.

Highway 12 takes its name from the road that traces Sonoma Valley, where Mission padres planted California's first vines in 1825. Its tasting room — 'The Barn,' just off the Plaza — pours the roadhouse-spirited Highway 12 and Highwayman wines: Sonoma red blends, Zinfandel, the Trailblazer.

Cochon and Odisea are the two labels of Adam Webb and Mike Kuenz, poured together at the Cochon Tasting Bar off the square. The focus is small-lot Rhône and Iberian varietals — Syrah, Pinot Gris, rosé — aged in French Hogshead barrels, with cheese and charcuterie on a covered patio.

Passaggio is Cindy Cosco's label, white-forward and built on an unoaked Chardonnay she first bottled in 2007. The downtown room pours her rosé, sparkling, and reds too, with a deck for sipping and live music on Saturdays.

Fulcrum is a Pinot house in the Sonoma Court Shops, where owner-winemaker David Rossi pours vineyard-designated bottlings from Gap's Crown, Brosseau, and Walala side by side. The room is small and the focus narrow. Dogs welcome.

Sosie — French for 'look-alike' — makes California wine in the image of the Rhône, the Loire, and Burgundy: Grenache Blanc and Marsanne whites, Pinot Noir, Syrah, picked early for acidity and restraint. The tasting room sits on Vine Alley, off the square. Built for the table.

Enoteca Della Santina is the wine bar beside the family's long-running trattoria, built around a 250-bottle wall of hard-to-find local and international labels poured by the glass. The full Della Santina's kitchen is available alongside. Regulars treat it as the town's living room.

Sojourn Cellars works from a quiet salon just off the square, pouring single-vineyard Pinot Noir, Cabernet, and Chardonnay side by side so the vineyards can be read against one another. Founded in 2001 by Craig Haserot and winemaker Erich Bradley. Friendly dogs welcome.

Kamen Estate is the downtown bar for Robert Kamen's Moon Mountain vineyard — the screenwriter planted it with the proceeds of his first script and farms it organically with Phil Coturri. The wines are mountain-grown Cabernet and Syrah, dark and structured. A block off the Plaza.

Pangloss Cellars fills a restored 1902 storefront on East Napa Street, named for the optimist of Voltaire's Candide. Winemaker Erich Bradley's Pinot, Chardonnay, and Grenache share the list with the Repris and Texture labels, poured in seated 90-minute flights with small-plate pairings.

SIGH is Sonoma's champagne bar, opened in 2012 by Sonoma native Jayme Powers after years with a California sparkling house. The list runs from grower Champagne to California sparkling and rosé, poured by the glass, the flight, or the occasional frozen slush. Walk in.

Corner 103 occupies a glass-walled corner on the Plaza, where founder Lloyd Davis runs a seated tour through seven Sonoma AVAs — each wine matched to a small bite. USA Today has named it among the country's best tasting rooms more than once.

The Sonoma Cheese Factory has anchored the north side of the Plaza since 1931, carrying what may be the Square's largest selection of gourmet cheeses and charcuterie from around the world. Wine flights come paired with that charcuterie or house-smoked meats off the patio smoker — the brisket among the best in town — alongside gelato flown in from Italy and, come summer, frosé blended from sparkling rosé and Champagne.

Three Sticks pours its estate Chardonnay and Pinot Noir inside the 1842 Vallejo-Casteñada Adobe, a half-block off the Plaza and restored by designer Ken Fulk. Tastings are seated, by reservation, and paired with small bites from El Dorado Kitchen. Adults only.