While it’s not a real castle, it’s the closest thing to a castle that’s in Washington DC!
The Smithsonian Institution Building sits on the National Mall between the US Capitol and the Washington Monument. Because of its look with the tall towers it’s also known as The Castle. It easily stands out among all the other buildings on the mall because of its architectural design.
The history of the Smithsonian Institution is an interesting one. It was founded from the donation of a British scientist, James Smithson. Smithson’s will left his estate to his nephew, Henry James Hungerford. However, the will stated that if Hungerford passed away and wasn’t married or have any children, that the money would then be given to the United States to start an educational institution in Washington DC that would be called the Smithsonian Institution. When Hungerford did pass away in 1835 he was not married and had no children, so the money was donated to the US. It took a little time, but finally in 1846 legislation was passed to establish the Smithsonian Institution.