The Smithsonian Institution Building - The Castle

Photo: ajay_suresh, CC BY 2.0 (cropped)

A stop on Washington DC National Mall Walking Tour, a free self-guided tour.

The red sandstone building with towers is the Smithsonian Institution Building, known as the Castle. Designed by James Renwick Jr. and finished in 1855, it was the Smithsonian's first building and once held everything: offices, a lecture hall, laboratories, exhibits and the home of the first Secretary, physicist Joseph Henry, and his family.

The Smithsonian exists because of James Smithson, an English chemist who never visited the United States. When he died in 1829 he left his fortune to found an institution for the increase and diffusion of knowledge. The bequest arrived in 1838 as 105 bags of British gold sovereigns, worth about half a million dollars, which the U.S. Mint melted down and recoined. In 1904 Smithson's remains were brought from Italy, and his tomb is just inside the north entrance.

The Castle closed in 2023 for its first major renovation in more than 50 years. It reopened briefly in summer 2026 and is scheduled to stay closed until 2027, but you can still walk through the Enid A. Haupt Garden behind it.

More on Wikipedia: Smithsonian Institution Building · James Renwick Jr. · Joseph Henry · James Smithson

Stops on this tour

1. Washington Monument
2. National Museum of African American History and Cu
   • The Corona - A Crown of Bronze-Colored Lace
   • History Galleries - From Slavery to Today, Bottom to Top
   • Emmett Till Memorial - The Casket That Changed a Nation
   • Contemplative Court - A Place to Pause
   • Culture and Community Galleries - Chuck Berry's Cadillac and More
3. National Museum of American History
   • Julia Child's Kitchen - The Real One, Pegboard and All
   • Star-Spangled Banner - The Flag That Survived Fort McHenry
   • Greensboro Lunch Counter - Four Students Sat Down
   • The First Ladies - Gowns, China and More
   • Ruby Slippers - Dorothy's Shoes from The Wizard of Oz
4. Smithsonian National Museum of Natural History
   • Henry the Elephant - The Rotunda's Giant
   • Sant Ocean Hall - A Right Whale Overhead
   • Hall of Fossils - Deep Time - The Nation's T. rex
   • Hall of Human Origins - Meet Your Ancestors
   • Hope Diamond - The Blue Stone with a Royal Past
5. National Gallery of Art
   • Ginevra de' Benci - Leonardo's Only Painting in the Americas
   • Vermeer Galleries - Quiet Rooms of Light
   • French Impressionists - Monet, Renoir and the Dale Gift
   • Multiverse - The Light Tunnel Between Buildings
   • East Building Atrium - Calder's Last Great Mobile
6. United States Capitol
7. United States Botanic Garden
   • Garden Court - Chocolate, Coffee and Vanilla
   • The Tropics - A Rainforest Under a 93-Foot Dome
   • Orchids and Medicinal Plants - Two Rooms Worth a Detour
   • National Garden - Roses and the First Ladies Water Garden
   • Bartholdi Fountain - A Centennial Survivor
8. National Museum of the American Indian
   • Native Landscape - Forest, Wetland, Meadow and Cropland
   • Potomac Atrium - Rainbows Under the Dome
   • Nation to Nation - Treaties and Broken Promises
   • Americans - Indian Names and Images Everywhere
   • imagiNATIONS Activity Center - Hands-On Play for Kids
9. National Air and Space Museum
   • Boeing Milestones of Flight Hall - The Bell X-1 and Friends
   • 1903 Wright Flyer - The First Airplane
   • Spirit of St. Louis - Lindbergh's Plane in a New Home
   • Destination Moon - Columbia and the Apollo 11 Crew
10. Hirshhorn Museum and Sculpture Garden
    • The Hirshhorn Building - Bunshaft's Concrete Drum
    • Belief+Doubt - Barbara Kruger's Wall of Words
    • Pickett's Charge - Mark Bradford's 400-Foot Battle
    • Hirshhorn Sculpture Garden - Reborn by Sugimoto
11. The Smithsonian Institution Building - The Castle
    • The Castle Exterior - Renwick's Red Sandstone
    • James Smithson's Crypt - The Founder Who Never Came
    • Enid A. Haupt Garden - A Garden on a Roof
    • Arts and Industries Building - The Mall's Second Museum
12. Freer Gallery of Art
    • Freer Courtyard - An Italian Garden Indoors
    • Peacock Room - Whistler's Blue and Gold Room
    • Asian Art Galleries - China, Japan, Korea and the Islamic World
    • Sackler Gallery Passage - The Museum Below the Garden
13. Jefferson Memorial
14. World War II Memorial
15. Martin Luther King Jr. Memorial
16. Korean War Memorial
17. Lincoln Memorial
18. Vietnam Veterans Memorial
19. White House Ellipse
20. White House
21. Lafayette Square