National Postal Museum

Located in the former City Post Office Building next to Union Station, this Smithsonian museum explores the history of the mail and the art of stamps. Opened in 1993, it displays historic mail planes and stagecoaches suspended overhead, along with rare stamps in the William H. Gross Stamp Gallery, one of the largest philatelic galleries anywhere. Exhibits trace the Pony Express, rural free delivery, and the logistics of moving letters across a growing nation. Interactive displays make it a family-friendly stop away from the crowded Mall.