A car is ideal for getting around the valley, and handy for getting here in the first place, although during the autumn harvest the main roads can crawl with tourist traffic. All the same, this is great driving country; treat yourself to a convertible and let the wind rush through your hair.
Direct flights from the UK land at San Francisco's International Airport (www.flysfo.com), which is a little more than an hour's drive from the southern end of the valley.
You can dine as you admire the splendid scenery if you travel on the somewhat touristy Napa Valley Wine Train that runs the length of the valley (www.winetrain.com); you'll still have to drive from San Francisco, though.
United States: 1. The area code for the Napa and Sonoma valleys is 707.
Napa Valley: The Ultimate Winery Guide by Antonia Allegra and Richard Gillette; The Silverado Squatters by Robert Louis Stevenson; East of Eden by John Steinbeck.
Do go / Don't Go
The exciting autumn harvest is known locally as 'the Crush'. You might want to time your visit and go just after or just before, when the weather is perfect and the crowds less madding.
Napa Valley is serious gastro territory, with some of the most sophisticated and delicious food in the States, much of it organic. There's a strong emphasis on French cuisine - this is definitely one place where you won't be offered 'Freedom fries'. As you'd expect, there's also a big emphasis on Californian wines, too. For some expert cookery demonstrations, visit the prestigious Culinary Institute of America's California campus in St Helena (www.ciachef.edu).
Black Tie Taxi (+1 707 259 1000) operates 24 hours a day and serves the entire Napa Valley area. Keep their number handy, in case you get too tipsy to drive home.
15-20 per cent is usual for almost every conceivable service - if in doubt, tip.
If you plan on hiring a convertible to breeze through the vineyards in, bring a headscarf or cap unless you want to arrive looking windswept and 'interesting'. A pair of sunglasses is a good idea, to dim the dazzling light on those mornings after you've overindulged.
There are almost 300 wineries to choose from; reservations are often essential. Friendly and informative tastings are offered at Del Dotto's caves (www.deldottovineyards.com) near Calistoga, while the views are a real bonus at Pride Mountain (www.pridewines.com). Connoisseurs should head for Swanson (www.swansonvineyards.com) in the Oakville District; the exclusive Altamura winery (www.altamura.com) in Wooden Valley; or Kuleto Estate (www.kuletoestate.com) in St Helena. Antique Tours Limousine Service (+1 707 226 9227) offes tours by knowledgeable guides in a classic 1940s Packard convertible.
Can't decide which winery to visit? The Vintner's Collective (www.vintnerscollective.com) in Napa offers tastings of wine from 20 Valley winemakers. It's $25 to sample six of the best. Smith members can get discounts and free tastings.
There are some excellent farmers' markets in Napa Valley during the summer months, selling organic local produce as well as wine. Check out Yountville's on Washington Street (Wednesday afternoons), St Helena's at Crane Park (Friday mornings) and Calistoga's on Lincoln Avenue (Saturday mornings). Lincoln Avenue has various arts and crafts shops, otherwise the downtown area of St Helena has more upscale boutiques.
Feast your eyes at Auberge du Soleil's restaurant (+1 707 967 3111) in Rutherford: the interiors are a bit dated, but if it's a clear day and you snag a table outside, you can have a perfect lunch with far-yonder vistas. Or ride the sky tram at Sterling Vineyards in Calistoga (+1 800 726 6136; www.sterlingvineyards.com) for a bird's eye view of the vines.
Combine culture with quaffing at Clos Pegase in Calistoga (+1 707 942 4981; www.clospegase.com), a postmodern temple to art and wine. Free guided tours of its grounds and winery are given daily at 11.30am and 2pm.
Late January-March Hot stuff is on the agenda at the Mustard Festival, a celebration of the valley's wine and food, as well as the wild mustard that carpets the vineyards (www.mustardfestival.org). Late July-early August Kino meets vino at the Wine Country Film Festival, with evening screenings in the vineyards (www.winecountryfilmfest.com). Early August Violins out for Music in the Vineyards - a string of chamber music concerts (www.napavalleymusic.com).