The Smithsonian Castle is iconic. It appears on the Smithsonian logo. Here is a short description of the building from the Smithsonian website.
Completed in 1855, the Castle is our signature building and home to the Smithsonian Visitor Center. As such, it makes a great starting point for your journey—here you can get a grasp of the scope and scale of the Smithsonian, see collections highlights from each of our museums, tour the Castle’s 19th-century architecture, see what’s going on today at all the museums, and consult with our in-house experts about what to see and do.On a recent visit, we found that the Visitors Center is high tech with animated displays and explanations of the museums and other exhibits.