George Vanderbilt didn't care for the city life as much as the rest of his family. So it was no surprise that after he visited the mountains of North Carolina, he eventually built his 250-room estate in Asheville. The Biltmore was completed in 1895, when he was still single. Vanderbilt married Edith Stuyvesant Dresser in Paris in 1898, and the couple raised their only child at Biltmore.

Descendants of the Vanderbilts still own and operate the estate as a for-profit company, and the home is now open to the public for tours. There's a 10,000-volume library, a bowling alley, a banquet hall featuring a 70-foot ceiling, an indoor pool and the artwork of Pierre Auguste Renoir and John Singer Sargent, among others.

Architect Richard Morris Hunt modeled the house after three 16th-century French chateaux. With more than 30 bedrooms, it's still shy of the 50 plus bedrooms at Downton's Highclere Castle. Still, Biltmore seems more than adequate for a house party.

Don't miss the butler's tour if you want to see how the other half lived on the estate. Modern guests can stay at an inn built in 2001 or a historic cottage that once served as the gardener's house.

The Bourns: Woodside, California

Filoli was completed in 1917 as the country estate for Mr. and Mrs. William Bowers Bourn, San Franciscans whose money came from water and gold. Filoli is just 30 miles outside San Francisco.

The European influence can be found all over the property: Tuscan columns in the portico, art from the Bourns' travels to Europe and even some of the house's walls. (The house library was copied from the library at Denham Place, a 1690s home in England.)

The expansive formal gardens were designed and constructed between 1917 and 1929. The next owners lived in the house until 1975, when the house and formal gardens were donated to the National Trust for Historic Preservation.

The Berwinds: Newport, Rhode Island

Downton fans might remember that the mother of American-born Cora, the countess of Grantham, had a home in Newport. That's where rich Americans summered, and it's where visitors can tour several grand homes at a time.

Mr. and Mrs. Edward Julius Berwind, who made their money in coal mining, built the Elms as their summer residence in Newport. Now one of the famous Newport Mansions and a National Historic Landmark, the Elms was finished in 1901. Unlike some residents of fictional Downton, who grudgingly adapted to modern conveniences like telephones and electricity, the Berwinds had the Elms outfitted with the latest modern conveniences. The house was among the first in Newport to be fully electrified with no gas backup. There was even an early ice maker.

The couple's art collection featured 18th-century Venetian and French paintings and Renaissance ceramics.

To get a good sense of life among the servants, the Preservation Society of Newport County, which owns and operates 10 historic properties in Newport, added an Elms servant life tour last year.