You'll have to pay for parking by the meter, but afterwards, it's free during the weekend.
Metered parking all around also after rush hour is free
There is meter parking on E street between 19th and 18th streets. Right in front of the Dept of Interior Building .
No parking garage in the area, but meter parking. Just check the sign as you park to see if you need paid the meter, because they will ticket you.
There are a couple within a block of the front door.
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