Horse Heaven Hills is above the only sea-level passage through the Cascade Mountains, linking growers there to both the marine environment of the Pacific Ocean and the semiarid desert of Eastern Washington.

Its warmer temperatures than in some areas of the state, such as the Yakima Valley appellation, make Horse Heaven Hills ideal for such varieties as merlot and cabernet sauvignon. At the same time, vintners are finding success with some white-wine varieties as well, such as chardonnay and riesling, said Kevin Corliss, director of viticulture for Ste. Michelle Wine Estates.

In addition, cool breezes that blow across the plain reduce the risk of disease and pests and create balanced fruit that is not too sweet or acidic, he said.

Winemakers often seek blocks of grapes that will provide a different taste, because of the soil, temperature or other climate features. True wine aficionados know exactly where the wine that touches their palate is produced down to the hillside.

That Horse Heaven Hills sits entirely inside the already-recognized Columbia Valley appellation speaks to growers and winemakers drawing even further distinctions for their products, Corliss said.

The region now includes four wineries, and more than 20 vineyards produce grapes for some of the state's premier wineries, according to the Washington Wine Commission.

Even the name for the region is unique.

In 1857, a Central Washington rancher followed the tracks of his escaped horses up a steep mountainside to find them munching grass atop a beautiful upland plain.

As the story goes, James Kinney proclaimed, Surely, this is horse heaven. More than a century later, the name for the region still stands

Horse Heaven Hills has more than 6,000 acres of vineyards, which are planted with more than 20 varieties of grapes, the majority of which are Cabernet Sauvignon, Chardonnay, Merlot, Riesling, Sauvignon Blanc, Sémillon and Syrah. Among the vineyards in the new AVA are Canoe Ridge and Champoux, which was planted in 1972 and is known for Cabernet. Grapes from Horse Heaven Hills are used by Andrew Will, Betz Family, Chateau Ste. Michelle, Hogue Cellars and Woodward Canyon wineries, to name a few.