Washington Monument cornerstone time capsule

At the Washington Monument's cornerstone-laying ceremony on July 4, 1848, organizers deposited a metal receptacle beneath the cornerstone that contained newspapers, coins, commemorative medals, and a portrait of George Washington; contemporary accounts record these items. The deposit, placed by the Washington National Monument Society, is commonly cited in historical descriptions as an early example of a time capsule associated with a national memorial. The box remained sealed within the monument's foundation through later construction phases and the monument's completion in the 1880s.