It is free parking and free entrance. During office hour, you could get map from the office and brief explanation of this place. The staffs are very friendly and happy to answer your questions.
It is free. There are no guided tours, though different groups such as the Audobon Society will have walking lectures and events.
Free parking, free entrance. There is a small office building with exhibition and I would guess, guided tours? But I was there after hours. Better to call in advance for more details
There's no fee.
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