Fourth-generation vintner Dario Sattui spent over 15 years and $40 million building an authentic 13th-century Tuscan castle on 171 acres near Calistoga, using centuries-old stone shipped from Europe. Opened to the public in 2007, the estate features 107 rooms, underground cellars, and a focus on Italian-style varietals reflecting Sattui's family winemaking roots dating to 1885.