Access? Yes. They also have elevators that travel to each floor.
Is the mummy exhibit always open? When I click on this weekend's exhibits its shows feline and a poem one.
I'm not certain they have chairs. I hope you're able to go, though! It's terribly special.
They do have two or three very basic collapsible wheel chairs, and if I recall, the entire museum is wheel chair accessible. The entrance is vehicle accessible(one way street), but parking is a short walk uphill.
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