I was able to get in immediately as a walk up. First responders, medical personnel, and military can skip the line of there is one.
It's gonna be Friday, it's extremely cold (below freezing weather) here (DMV) expect the unexpected - this being said, come prepared - I highly recommend starting your museum journey at the entrance a few minutes before your scheduled time passes.
Not lines at all!
No lines are not long to get in. Maybe long for certain exhibits.
Not long lines, shouldn't expect to long of a wait, especially if you're planning arriving at ten. Although I've only been there once. Not from DC myself.
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