You only pay to have a tour of the mansion, as walking the carriage road trails and walking around the grounds of the property is free. The only thing you have to pay for is a ticket for a tour of the mansion, which are already discounted for those 62 and above, at $4, whereas its $8 for adults. So while having the senior annual pass does not get you any discounts, being 62 and above does help you, because you can get a discounted ticket.
I think you are referring to the national park pass?
You should be able to, yes.
I would ask at the customer service desk. I personally don't know.
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