High Valley is a rare transverse (east-west) valley in the California Coastal Range, and one of only two producing quality wine grapes the other being the Santa Ynez Valley near Santa Barbara.

One mile wide and five miles long, High Valley sits 1800 feet above sea level. Flanking the southwest borders of High Valley is Clear Lake, California’s largest natural lake. Clear Lake acts as a giant air conditioner to further cool the marine influenced westerly winds blowing in from the Pacific Ocean. This lake cooled wind rises off the lake and settles into the High Valley, contributing to evening temperature swings as great as 40 to 50 degrees, creating the perfect conditions for the slow ripening of grapes. This brings out the complex characteristics of the fruits, translating into world class fruit.

During Lake County’s active volcanic period, lava from the now-extinct Round Mountain volcano built up the eastern side of High Valley, and eventually dammed the preexisting creek. With no outlet for hillside runoff, a lake formed in the depression west of the volcano until it crested at the lowest point. Alluvial sediments washed down from the hills and filled the canyon. Over time, the channel was eroded and the lake drained naturally, leaving behind the large basin plain of High Valley.