The Columbia Gorge AVA is found in the Columbia Gorge. This region straddles the Columbia River, and thus lies in both Oregon and Washington; it is made up of Hood River and Wasco counties in Oregon, and and Klickitat counties in Washington. The region lies to the east of the summits of nearby Mount Hood and Mount Adams, situated in their rain shadows; thus, the region is significantly drier than the Willamette Valley. It also exhibits significant differences in elevation due to gorge geography, and strong winds common in the area also play a factor in the region's climate. This allows a wide variety of grapes to be grown in the Columbia Gorge. The region has nearly 40 vineyards, growing a wide variety of grapes, including Syrah, Pinot noir, Chardonnay, Gewürztraminer, Zinfandel, Cabernet Sauvignon, Pinot gris, Riesling, and Sangiovese.