Filoli, Woodside, California

According to architect and author Gary Lawrance, an expert on grand residences, this Georgian mansion is a splendid example of American mansion style. Blending regional details, such as a tiled roof that is typical of California, with traditional architectural features, architect Willis Polk created the masterpiece for gold-mine owner William Bowers Bourn II, completing it in 1917. Its formal gardens remain a draw to visitors and its exquisite interior was featured in the television series, Dynasty.