One of the newer museums in the Smithsonian collection, the National Postal Museum occupies the space that was the City Post Office Building from 1914 to 1986. The 100,000-square-foot building houses a 35,000-square-foot exhibition space, a 6,000-square-foot research library, a museum shop and a stamp store, perfect for collectors. Inside, the museum houses collections of stamps that have been collected since 1886, with nearly 6 million items in the collection. The museum is open daily (except Christmas) from 10 a.m. to 5:30 p.m., and offers free admission.
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