Willamette Valley, in western Oregon, is one of the United States' most important non-Californian AVAs. From the city of Portland, it stretches southwards for 120 miles (190km) down the eponymous river valley, covering some 3.3 million acres (1.2 million ha) of land. Pinot Noir is by far the most popular and top-performing variety here. The best Oregon Pinot Noirs are regularly compared to their significantly more expensive counterparts from Burgundy.
The fertile Willamette Valley has been the most densely populated area of Oregon since pioneers began to settle in the early 19th Century. Viticulture began in earnest here in the late 1960s, when students from the University of California's Davis campus looked north for inspiration, finding the climate in California unsuitable for Pinot Noir. In 1979, a Willamette Valley Pinot Noir beat a host of wines from Burgundy to take a place in the top three at the Gault-Millau French Wine Olympiades. This made the world take notice of Oregon and the Willamette Valley; vineyard plantings and international interest have increased steadily ever since.
The valley follows the path of the Willamette River, a tributary of the larger Columbia River that marks Oregon's northern border with Washington. The Cascade mountain range forms the valley's eastern border and the Oregon Coast Range on the western edge runs between the Willamette and the Pacific Ocean. Wine is produced throughout the valley, but the greatest concentration of vineyards is in the hills just south-west of Portland.
Although much of the Pacific's influence is blocked by the Coast Range, the climate in the Willamette Valley can be considered as maritime, with ocean breezes seeping in through a series of gaps in the mountains. Rain falls mostly in the winter, and long, dry summers with ample sunshine and cooler evenings provide an excellent ripening situation for the vines. The threat of rain in autumn means that longer-ripening grapes such as Sauvignon Blanc have not thrived in the climate here, which is better suited to the earlier-ripening Pinot Noir. In fact, these rains and the general changeability of the climate can play havoc with the crop, and vintages in the Willamette Valley can be as variable in quality as those in Burgundy.
Most of the region's vineyards can be found on the many hills in the valley, where the soils are less fertile and there is less risk of frost. These hills are the result of tectonic shift and ancient lava flows and are characterized by their red, iron-rich soils known as Jory, a type so distinctive to the Willamette Valley that it has become Oregon's official state soil. Other viticultural parts of the valley benefit from ancient sedimentary soils, and the valley floor is covered in fertile silt, the result of massive Ice Age floods that swept through Washington's Columbia Valley before settling in the Willamette Valley. This fertile soil is not suitable for viticulture, but supports Oregon's other important crops: hazelnuts, Christmas trees and hops for the production of beer.
The Willamette Valley became an AVA in 1984. In 2002, a group of producers banded together to mark out and petition for the creation of six new AVAs within the Willamette Valley to celebrate the diversity of the terroirs here. As a result, the Dundee Hills, McMinnville, Eola-Amity Hills, Yamhill-Carlton District, Chehalem Mountains and Ribbon Ridge sub-AVAs were established between 2004 and 2006.
The newest AVA here is Van Duzer Corridor, which was granted official status in late 2018. The topography of the area funnels coastal winds, creating conditions considered specific enough to warrant its own appellation. Van Duzer Vineyards is the dominant producer here.