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Smithsonian Castle - Washington, D.C. -

This Norman-style castle was built from red sandstone in 1855. It served as the office and home of the first Secretary of the Smithsonian, Joseph Henry. Today it's where you'll find the Smithsonian Institute's visitor center.

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Hammond Castle - Gloucester, Massachusetts -

Inventor and scientist John Hays Hammond is the man who ordered the construction of this English-inspired castle in 1926. Inside he'd store his collection of Roman, medieval, and Renaissance artifacts.

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Biltmore Estate - Asheville, North Carolina -

Set in the Blue Ridge Mountains, this 19th-century estate built by George Vanderbilt is America's largest privately-owned residence. From beautiful gardens to a winery and a huge library, Biltmore Estate is a historic house museum and tourist attraction worth visiting.

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Castello di Amorosa - Calistoga, California -

Designed by Dario Sattui, this may seem like it was built in medieval Tuscany, but it was not completed until 2007. Set in Napa Valley, Castello di Amorosa is best known as a winery.

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Castello di Amorosa - Calistoga, California -

The castle features 107 rooms, most of which are used for winemaking. In addition to tasting great wines here, you'll get to experience some of the castle's medieval features, including a dungeon and a drawbridge.

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Hearst Castle - San Simeon, California -

Hearst Castle was built by newspaper mogul William Randolph Hearst. Completed in 1947, "The Enchanted Hill" boasts four buildings and a total of 165 rooms.

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Hearst Castle - San Simeon, California -

One of Hearst Castle's most impressive features is its outdoor Neptune Pool. There is also a magnificent indoor Roman Pool, and plenty of artwork and exquisite artifacts to marvel at.

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Gillette Castle - East Haddam, Connecticut -

This medieval-inspired castle showcases striking stones and impressive woodwork, and boasts amazing views over the Connecticut River. It was conceptualized by actor William Gillette, and construction was completed in 1919.

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Iolani Palace - Honolulu, Hawaii -

Built in 1882 by King Kalakaua, Iolani Palace is Hawaii's official royal residence. The palace is the sole example of American Florentine style (a mix of Italian Renaissance and Hawaiian architecture).

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Bishop Castle - Rye, Colorado -

Jim Bishop built Bishop Castle, single-handed, in 1969. The craftsmanship is absolutely amazing and is definitely worth a visit (which is completely free of charge, by the way).

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Lyndhurst Mansion - Tarrytown, New York -

This Gothic-style mansion was designed by architect Alexander Jackson Davis and built in 1838. Lyndhurst Mansion has been open to the public as a museum since 1965.

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The Breakers - Newport, Rhode Island -

The former summer residence of the Vanderbilt family was completed in 1895. It was inspired by 16th-century Italian architecture and features 70 rooms. 

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Loveland Castle - Loveland, Ohio -

Loveland Castle was built by Boy Scout troop leader and World War I veteran Harry Andrews. Construction began in 1927, and took over 50 years to complete.

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Belvedere Castle - New York City, New York -

You'll find this folly from 1857 right in the heart of the city, in Central Park. With the Manhattan skyline in the background, this place really feels special.

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Bannerman Castle - Pollepel Island, New York -

Set in an uninhabited island in the Hudson River, Bannerman Castle was built in 1901 by Scottish immigrant Frank Bannerman, who drew inspiration from Scottish medieval fortresses. Bannerman used it as a warehouse for his military supply company. In 1920, tons of shells exploded, destroying great part of the castle.

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Bishop’s Palace - Galveston, Texas -

Built in 1892, this four-story building was designed by architect Nicholas Clayton for an affluent attorney. Bishop’s Palace is also known as Gresham House.

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Boldt Castle - Alexandria, New York -

Construction of this castle on Heart Island began in 1900 by hotel magnate George C. Boldt. The castle was a gift to Bolt's wife, but a few years later she died and Bolt never finished it. In 1977, Thousand Island Bridge Authority purchased Heart Island and completed the castle.

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Grey Towers Castle - Glenside, Pennsylvania -

This 19th-century castle was the home of American businessman and sugar magnate William Welsh Harrison. Grey Towers Castle is now part of the Arcadia University campus.

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Joslyn Castle - Omaha, Nebraska -

Joslyn Castle was designed by architect John McDonald and built in the Scottish Baronial style in 1903. It was the home of entrepreneurs George and Sarah Joslyn.

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Thornewood Castle - Lakewood, Washington -

Chester Thorne, one of the founders of the Port of Tacoma, bought a manor in England and shipped every brick to Lakewood to build a castle for his wife. Thornewood Castle is known as "the house that love built."

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Marble House - Newport, Rhode Island -

This Gilded Age mansion inspired by the Petit Trianon château at Versailles was completed in 1892. Alva and William Kissam Vanderbilt were the owners.

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Marble House - Newport, Rhode Island -

It features 500,000 cubic feet of marble, hence the name. It really looks grand!

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Singer Castle - Chippewa Bay, New York -

Built in the 20th century, this castle on Dark Island was formerly known as "The Towers" and "Dark Island Castle." It boasts 28 rooms, numerous artifacts, and secret passageways!

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Fonthill Castle - Doylestown, Pennsylvania -

Fonthill Castle was completed in 1912 and became the home of archaeologist and tile maker Henry Chapman Mercer. Its rooms are filled with hand-crafted ceramic tiles.

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Kentucky Castle - Versailles, Kentucky -

Set in the Kentucky blue hills, this castle is truly magnificent. Built in 1969, it now operates as a hotel.

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Curwood Castle - Owosso, Michigan -

Curwood Castle was built in 1922 by author James Oliver Curwood next to his home on the banks of the Shiawassee River. Inspired by Norman French chateaus, the castle is now a museum.

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Castle in the Clouds - Moultonborough, New Hampshire -

Built in 1913 by shoe manufacturing mogul Tom Plant, this historic mansion didn't open to the public until the 1950s.

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Montezuma Castle - Camp Verde, Arizona -

Established in 1906 on a cliff in Camp Verde, Arizona, Montezuma Castle National Monument is a unique example of Native American culture. It  protects a set of dwellings built and used by the pre-Columbian Sinagua people sometime between 1100 and 1425.

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Ha Ha Tonka Castle ruins - Camdenton, Missouri -

Located in the Ha Ha Tonka State Park, these ruins belong to a castle built between 1905 and 1922. The European-style castle was built by Kansas City businessman Robert Snyder.

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Victoria Beach Castle - Laguna Beach, California -

A castle on a beach in Southern California? Well, sort of. Also known as "Pirate's Castle," this is a tower built in 1926 into a cliffside. It's still worth a visit though!

Sources: (Time Out) (Only in Your State) (Travel + Leisure)

See also: Breathtaking castles that look straight out of a fairy tale

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