National Postal Museum
We couldn't skip the Smithsonian entirely, but we assume you know about the most popular spots. This quirky little sister of the group, located near Union Station, promises a good time, even for non-philatelists, with exhibits including items salvaged from the Titanic and the Hindenburg.
Where: 2 Massachusetts Avenue NE; 202-633-5555.
When: Daily, 10 a.m. to 5:30 p.m.

Free Summer Saturdays at the Corcoran
Until September, the Corcoran Gallery of Art is waiving the usual $10 admission fee every Saturday. At present, a new exhibition featuring painter Richard Diebenkorn is generating major art-world buzz, and there are tons of free activities and programs going on, as well.
Where: 500 17th Street NW; 202-639-1700.
When: Saturdays, 10 a.m. to 5 p.m., through September 1.


Photo: Courtesy of National Postal Museum