If you go to the museum on a day where they are not holding an event, going through the entire museum will take about an hour. If you do go on an event day; Italian car day, Japanese automobile day, German car day...expect go be there for at least 2+ hours. Personally I'd wait for an event day to go because most of the time there is no entrance fee and the museum is open to the public. Might run into longer lines for thd actual museum, but hundreds of cars show up which just adds to the amazing experience.
I've been there when it was very busy. We walked through the museum in about 90 minutes and then spent around the same time walking the gardens. Both are worth the time.
If you love photography and reading about car information, it takes more than 2 hours. The place is great and fun.
the museum itself its not that large, you can go through the main exhibit in 30-45 min depending on how much you look/read. the garage below has a ton of cars and information so it might add an hour or so, but you mileage might vary,.depending on your curiositt on the subject matter, and the Anderson's familiar history. plan for at least an hour and a half.
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