The Jura is sandwiched between Switzerland and Burgundy, and its vineyard area is the first upland between the Bresse Plain and the Jura Mountains. The lower slopes have more clay to go with marl; the higher slopes have more limestone, much like Burgundy's Côte d'Or on the other side of the vast plain. The influence of the Alps ensures that Jura's climate is decidedly more continental than Burgundy's, and winters can be quite cold. Vines are trained high for added protection against frost. Harvest typically runs well into October.
This is an ancient grape-growing region whose wine was referenced in 80 AD by Pliny the Younger. The early 19th century supported close to 50,000 acres of vines. Largely because of the phylloxera epidemic, the total today is around 4,000 acres. The earlier century supported a far greater diversity of vines too—42 different kinds, according to one count—whereas today five varieties dominate. Chardonnay is the most important at 43% of the total vineyard surface, and came from Burgundy with its sibling Pinot Noir as long ago as the 10th century. Savagnin, a distinctive wine prized for vin jaune, accounts for 22% of the vineyards; Poulsard, aka Ploussard, adds up to 14%; Pinot Noir for 13%; and Trousseau for 8% (figures come from a census taken in 2000).