Charles Krug is (also) in Nappa Valley:

Quality wine begins in the vineyards. It only makes sense that if you want to make great wines, you first invest in the best grapes. Welcome to the world of the Peter Mondavi Family, proprietors of the Napa Valley’s oldest winery, Charles Krug. Collectively, the family owns and farms more than 800 acres of prime Napa Valley vineyards. Strategically located in some of the most coveted regions of the world-famous Napa Valley and farmed exclusively under the direction of the family to ensure quality standards, these vineyards are the corner piece of Charles Krug Winery’s success.

Read this about "your" Charles Krug, looks like it is top notch:

The steep price paid by LVMH can be attributed to a strengthening market for prestige wine brands, but also to Krug's huge stock of mature and maturing Champagnes, estimated at about 300,000 cases. Under the direction of brothers Henri and Remi Krug, the house has pursued a policy of quality. All Champagnes in Krug's lineup (except Krug Rosi) age for at least six years on their lees, or sediments, in the cellars before release, making them distinctively rich and flavorful. Krug bottlings age beautifully for over a decade after release, and have a cult status among aficionados who are willing to pay triple-digit prices for these exclusive wines.