Yes they give military discounts I'm not sure about the senior citizens.
Yes I believe discounts for military. My wife says yes. $5.00 discount on a season pass.
If you are over 62 you can get a discounted National Park pass.
Dude it's free. Well the tour was. But then again I was there in the off season. I think there is a small charge during the rest of the year to travel on the road to the fort. I was there in February and it was totally free once you paid $1.00 toll fee to enter the beach area. There is a small fee of $1.25 to be on the 1/4 mile pier. It's well worth it. It's to maintain it.
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