Smithsonian Institution Building Smithsonian Institution Building The Smithsonian Institution Building, located near the National Mall in Washington, D.C. behind the National Museum of African Art and the Sackler Gallery, houses the Smithsonian Institution's administrative offices and information center. The building is constructed of Seneca red sandstone in the faux Norman style (a 12th-century combination of late Romanesque and early Gothic motifs; built in the Gothic and Romanesque revival styles) and is nicknamed The Castle. It was completed in 1855 and designated a National Historic Landmark in 1965. The Castle was the first Smithsonian building, designed by architect James Renwick, Jr., whose other works
Cooper Hewitt, Smithsonian Design Museum made of Tiffany glass, was renovated in 1975. In 1995, the museum closed for a year for a $20 million renovation to connect the three buildings on the property, improve accessibility, and build a design study center. Funds for the 1995 renovation project included $13 million from the Smithsonian Institution and a $2 million donation by Agnes Bourne. In 2008, the museum started to undergo renovations. The renovation costs $91 million and is the largest in the museum's history. The renovation was partially financed by the museum endowment. The museum reopened on December 12, 2014. Additional renovations were completed in