Willy Wonka's golden ticket and Batman's mask are among some 30 movie costumes and props given Friday to the National Museum of American History in the US capital.
US production company Warner Bros. donated the items, which come from 13 feature films that came out between 1942 and 2005.
The memorabilia will join the museum's permanent entertainment collection, where Harry Potter's wizard robe and Dorothy's ruby slippers are already on display.
"To tell American history, we are looking for objects that made a mark on their time -- and movie costumes are among them," said museum director John Gray.
Joining the Caped Crusader's mask -- worn by George Clooney in 1997's "Batman & Robin," -- was a golden ticket and three chocolate bars used in the 2005 remake of "Charlie and the Chocolate Factory."
Warner Bros. has also sent over one of the Gremlins from "Gremlins 2: The New Batch," as well as Halle Berry's sexy catsuit from 2004's "Catwoman."