While America does not have "medieval" castles built for feudal defense, it has numerous Gilded Age "castles" built by millionaires in the late 19th and early 20th centuries as displays of wealth. Examples include the Biltmore Estate in North Carolina, which is the largest private home in the US, and Hearst Castle in California. There are also unique architectural "follies" like Gillette Castle in Connecticut or Bannerman Castle in New York. Unlike European castles, these were constructed using modern techniques to mimic European Gothic or Renaissance styles. Additionally, there are older stone fortifications like Castillo de San Marcos in St. Augustine, Florida, which was built by the Spanish in the 1600s. While these serve a defensive purpose, they are technically "forts" rather than the residential/military hybrid known as a classic European castle.