Tucked away in the far eastern corner of Sonoma County is the lesser-known Knights Valley appellation. Established as an American Viticultural Appellation (AVA) in 1982, today, the area has been fortunate to retain its rural look, with a sparsity of residences and wineries. While the valley and hills are dotted with vineyards, the overall quiet solitude of the region remains intact, offering a welcome, calming sense of place.
Knights Valley is overshadowed by the more recognizable AVAs—Alexander Valley to the northwest and Napa Valley to the southeast. Mount Saint Helena, seen from much of Sonoma and Napa Counties, is the towering landmark of Knights Valley.
The beautiful valley and imposing mountain have always attracted settlers: the Onasatis (Wappo) tribe arrived at least four thousand years ago, followed by the Spanish. Peter Michael Winery owes its favored position here—rooted in prized rhyolitic soil and enjoying one of the best wine-growing climates on earth—not only
to geographic and geologic forces but also to the people who came before.
Despite its relative youth and volcanic rock, Mount Saint Helena is not a volcano. Geologists believe that a widespread system of fissures and vents laid down heavy layers of volcanic materials, and later, faulting raised the mountain. Along with silica-rich rhyolitic soil coveted by winegrowers, the volcanic vents distilled and deposited valuable elements that attracted miners and created hot springs that warmed the imaginations of entrepreneurs.