A California millionaire built a massive '13th-century Italian castle' in the middle of wine country - take a look inside

Napa Valley has been called the Disneyland of wine country, with good reason. It's essentially a boozy amusement park for adults, with elite wineries and resorts packed along a highway.

Another reason for the comparison: The region has its own medieval castle.

Nestled in the rolling hills of Castiloga, California, Castello di Amorosa is a world-class winery based out of a replica of a 13th-century Tuscan castle. The owner, Dario Sattui, is a fourth-generation wine-maker and ardent Italophile who spent $40 million to bring a slice of the old country to Napa Valley. At 142,000-square feet, the castle took more than a decade to build.

We recently took a guided tour of Castello di Amorosa. Here's what it was like.