Built on its own island in the St. Lawrence River, Boldt Castle was commissioned by George C. Boldt, a millionaire hotel magnate, for his beloved wife Louise. Located on Heart Island near Alexandria Bay, New York, work on the castle was begun in 1900. Three hundred workers, carpenters, stonemasons, and artists all worked on the 120-room, six-story castle. Work stopped in 1904 when Mrs. Boldt suddenly died. It lay empty at the mercy of the elements until 1977 when the Thousand Island Bridge Authority acquired it and began its restoration. It is now open to the public.
America's only royal palace, 'Iolani Palace is the former home of King Kalakaua and his sister Queen Liliuokalani. King Kalakaua had it built in 1882 in what is now downtown Honolulu. King Kamehameha III made this site his official residence in 1845, but the history of the site fades into antiquity as possibly the site of an ancient place of worship. The palace grounds also contain the tombs of several Hawaiian kings and others of importance. The palace is open for tours.
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George Washington Vanderbilt, the youngest son of railroad and steamboat tycoon William H. Vanderbilt, inherited his fortune from his father. In 1889 he put some of that inheritance to work in the construction of the largest private residence in the United States. The 250 rooms include 35 bedrooms, 43 bathrooms, an indoor swimming pool, exercise room, 65 fireplaces, and covers four acres. Situated near Asheville, North Carolina, it is still a private residence owned by George Vanderbilt's descendants, but open to the public.
John Hays Hammond, Jr., known as "The Father of Remote Control," built his castle from 1926-1929 as a wedding present for his wife Irene, and to house his collection of Roman, Renaissance, and medieval artifacts. Second only to Thomas Edison, John Hammond, Jr. created ideas for over 800 inventions and held over 400 patents. A self-guided tour takes the castle-goer through the great hall, the Renaissance dining room, two guest bedrooms, the inventions exhibit room, kitchens, library, and other parts of the home.
Henry Chapman Mercer was an American archaeologist, anthropologist, antiquarian, and ceramist. He built Fonthill Castle between the years of 1908-1912 in Doylestown, Pennsylvania. Serving as his home, the castle is an eclectic architectural mix of Byzantine, Gothic, and Medieval styles. It also houses his collections of prints and tiles. The castle used the poured-in-place concrete style, and has 44 rooms with over 200 windows. It contains many pieces of built-in furniture and many decorative tiles that Mercer made. On his world travels, Mercer collected other artifacts that include cuneiform tablets found in Mesopotamia that date to before 2300 BC. On the National Register of Historic Places, Fonthill Castle is open to the public.