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.