Dario Sattui owns his own castle, a baronial keep atop a hill in Calistoga complete with a Great Hall for sumptuous banquets, a royal apartment, and a Grand Barrel Room with a cross-vaulted ceiling made of ancient handmade bricks.

But if a man's castle is truly where he hangs his hat, that would be for Sattui a 19th-century Queen Anne mansion at the bottom of the hill. It is a lot more modest, but only by comparison to the spectacular Castello di Amorosa that the longtime Napa Valley vintner built out of his passion for Italian medieval architecture.

When Sattui bought the 170-acre property, a fairy-tale setting with forested hills, streams and a small lake, it came with a coveted permit for a 250,000-case winery. The previous owner also had secured the last open public-tasting permit granted in Napa Valley in 1989. It was a vintner's dream.

Sattui, however, wasn't interested in that. And a castle was nowhere on his horizon. It was the old house and the land, a beautiful slice of Napa Valley history, that he was after.

"I bought this property because of this house. I had no intention of building a castle," said Sattui, leaning his 6-foot, 5-inch frame against one of the spindled columns along the massive covered porch of the mansion. "It has so much architectural detail. So much character. I love this house."

While Sattui loves entertaining the public and celebrities like Arnold Schwarzenegger and Rachael Ray at his castle, his own home remains a rather secret gem set among maples and other mature trees down an unpaved frontage road to the south of the castle.

The castle is new, built authentically to fool the eye. But this three-story, 8,000-square-foot Victorian, long a visual landmark along St. Helena Highway, is the real deal.

It was built between 1875 and 1877, primarily by Prudence Shamp, whose husband Thomas was away looking for a big strike in Nevada. He died in 1875 and Prudence lived there until she sold it, along with 375 acres, to Martin Holje, who added to it and renamed it "Maple Wood."

The historic mansion is the clear showstopper in the "Through Doors and Gates" Calistoga home tour on Sept. 28. A benefit for the Sharpsteen Museum, the tour will give visitors a snapshot of Napa Valley living between 1870 and the present.

Other stops include the Lillie House, an 1870 Gothic Revival on Cedar Street that is the oldest house in Calistoga; a "Pastor's Cottage" built in 1880 next to what was then a Methodist church (now the home of John and Pat Merchant, owners of Indian Springs Resort); an Arts and Crafts-style artist's compound on Fourth Street; and a two-story contemporary Craftsman house on Washington Street with works by Calistoga's famed Old World artisan Carlo Marchiori.

Sattui's mansion is known to valley dwellers as Villa St. Michael, said Kathy Bazzoli, a member of the board of directors of the Sharpsteen Museum of Calistoga History and a native of Napa Valley. The Forni family, which bought the house in the 1940s, named it after a church in their native Lombardi near Lago Maggiore in Italy.

Sattui bought the old estate 20 years ago from Dr. Andrew Bosc. He couldn't afford the $10 million price tag, but when the housing market dropped he closed the deal for about $3 million, including some of the furnishings.

Since then, he's spent another $3 million in renovations, lifting it up to replace the foundation, remodeling the kitchen and bathrooms, refinishing doors, commissioning frescoes and faux finishes, and extending the porch so it wraps completely around the house. There are now 3,000 square feet of covered porch from which to enjoy scenic views of the Napa Valley floor.

There are 20 rooms, but Sattui said he lives in only a handful of them.

It was the history of the property that also intrigued Sattui, who only recently legally changed his name from Daryl to Dario in salute to his Italian roots.

The land was first inhabited by two Wappo Indian villages attracted to the fresh stream, he said. It was first developed by William Houston Nash, who traveled to Calistoga by covered wagon in 1846. The house he built in the 1840s still stands beside the grander mansion, all owned by Sattui.

You can reach Staff Writer Meg McConahey at meg.mcconahey@pressdemocrat.com or 521-5204.