Make reservations online, or go to the museum like I did and hope that you'd get tickets at the entrance as I got.
Mark's advice is the best.
As soon as same day online reservations open that morning, keep clicking even if you get errors. I even received no tickets available but it didn't seem right tried again and reserved 4 tickets for later that day.
Go to the online website. If you are staying at a hotel, ask the concierge for assistance. The sooner the better. If you have not arrived at your hotel, call ahead.
Online is the best way to go.
To the web guess go to the website just as he said but to secure the tickets. Do it early in morning like around 630 am the earlier you try will be the most successful.
A popular Spring weekend, definitely online ahead of time. If its raining like crazy, you might get day of.
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