Yountville is in the middle of the Napa Valley, which makes it a useful base for the rest of the wine country. Napa city is fifteen minutes south, St. Helena fifteen minutes north, and Sonoma County over the hill to the west. The Silverado Trail running parallel to Highway 29 is the back road with most of the appointment-only wineries.
For a non-wine day, the redwoods of the Russian River area and the coastline at Bodega Bay are both about ninety minutes west.