The main hall with Polynesian artifacts was very enlightening and we really learned a lot about the history of Hawaii. It is well worth spending a couple of hours here.
We found the science hall and the planetarium show to be kind of juvenile for a 30 something couple, but I know kids would like them and would highly recommend this for families. If you're just adults, I say spend 2 hours in the main hall and call it a morning.
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