Street parking if you go early enough, $2.30 per hour (loose change or credit card), some spots are 2 hour limit, some are 3. You can leave the museum to feed the meter, but you have to get back inline and show your original reserved museum pass to get back in.
Street parking 2 Hours 4.65$
We used the SpotHero app to get lots of parking options all around the National Mall.
Street parking is available.
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