Almost three-quarters the size of France, California accounts for nearly 90 percent of American wine production.  The production in California alone is one third larger than that of Australia.  If California were a separate country, it would be the world's fourth-largest wine producer.

Occupying the southern two-thirds of the country's west coast (Oregon and Washington make up the rest), it spans almost ten degrees of latitude and 850 miles (1370km) of coastline. With mountains, valleys, plains and plateaux, the state's topography is as complex as its climate, offering winegrowers a bewildering choice of terroir.

The state's viticultural history dates back to the 18th century when Spanish missionaries planted the first vineyards to produce wine for Mass.

Today, California hosts some of the world's largest wine companies, but it is also home to a number of boutique wineries, some of which attract astronomical prices for their cult wines. 

The principal varieties grown in California are Cabernet Sauvignon and Chardonnay.  A wide range of traditional European (Vitis vinifera) vines also flourish, grafted to hardy, phylloxera-resistant American rootstocks.  Less well known are American/European hybrids producing wines mainly for local consumption.  Many French Champagne houses have set up wineries in California.  The most famous examples are Moet & Chandon's Domaine Chandon, Taittinger's Domaine Carneros, Louis Roederer's Roederer Estate in the Anderson Valley and Mumm Napa in the Napa Valley.