There was no cost, BUT, It's not open to the public.
You can only go when they have open house events. I am not sure if there is a charge for that though. I got to go on a family day which was free because my father in law is a volunteer there.
I went on a school trip. Dont remember if we had to pay for the trip. Try calling or check their website. Sorry wasnt able to answere your question.
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