It's best to book online in advance. I believe they are booking for October or November now. They do have same day tickets, but you have to be there before 6:30a to stand in line and they run out quickly.
Please go online and get free tickets in advance. 'Same day' tickets may be depleted. Please get them days in advance. Overcrowding cause many to be turned away.
We were there just this past May. They had what they called Walk-up Wednesday and we got to get in with no ticket. I'm not sure what they're offering now, but its always good to look online and I mean at 6am look on line because they go fast.
It's free to attend any of the Smithsonian Institute museums in DC. You can however receive VIP tickets from your local congressman or one of the sponsors of the museum.
Tickets for what
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