It all depends. If you're just looking at the collections, you could probably do it in 4-5 hours. If you plan to catch a couple of demonstrations and do the make your own glass, I would allot for more time. Especially if you want something from the gift shop to take with you. Museum tickets (remember to buy in advance on their website) are good for 2 consecutive days, so there is that to keep in mind as well.
If you looking for a quick drop in and gift shops only - maybe 1-2 hours (depends on how fast you shop.) To do the whole museum - 4-5 hours at least
Everyone gave great advice... I agree with it all!
I would say 4-5 hours
We were there 11-4 with a stop at the cafe for lunch, and we still missed parts.
I would say maybe 4 to 5 hours? If you're going and stopping here and there to look at pieces or visit the cafe for lunch. (Which has good food!) We went just last week
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