If you visit there is a resident park caretaker home and garage on north side of park. Go and ask about your reservation needs. They will be very helpful.
Public is free to visit this site during hours posted. I agree with j, the museum is a good stop and if you can catch a tour its very informative. Are you asking about reserving for a gathering? I am not sure there are facilities for that anymore at this site.
It is free, no reservation needed but if you like to visit the museum (recommended), better check the hours in their website.
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