Free on line
Check the national museum website for tickets.
Inorder to get ticket go on web site & u will need to b prepare to request tickets 2 or more months in advance. Tickets r free. It's an amazing experience
Check online day of at exactly 630am
The tickets are free, my wife got ours. I'm pretty you can download the tickets from the museum's web site. There can be a waited period for availability. You can "roll the dice" and try and get them at the door but like I said it is a gamble because they may not be available. You can't take it all in ,in a day so get two days if you can.
Recently they stopped requiring tickets to go. You can just go in like any other Smithsonian museum
Go online at 6:30 in the morning.
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