My daughter and I are arriving in Bar Harbor a week from Friday (first time visitors, REALLY looking forward to it). We are not renting a car; we're planning to use the Island Explorer. I know that we need to pay park entrance fees; and I have no problem with that. Anyway, my question, how does that work with the Explorer? Do we buy one park pass each, and just bring it with us on the Explorer?? I know, stupid question... thanks!