The Smithsonian Institution comprises 17 museums in Washington as well as two museums in New York, which, taken together, truly span the world and the ages. The holdings of the nation's attic are estimated at 137 million objects. Visitors usually start in the institution's first building, The Castle, which holds a general information desk for all the institution's museums and the crypt of James Smithson, a British scientist and the original benefactor (1000 Jefferson Dr. S.W.).
Completed in 1855, the original Smithsonian Institution Building was designed by architect James Renwick Jr., whose other works include St. Patrick’s Cathedral in New York City and the Smithsonian’s Renwick Gallery in Washington, D.C. This Washington landmark is constructed of red sandstone from Seneca Creek, Maryland, in the Norman style (a 12th-century combination of late Romanesque and early Gothic motifs).