Thanks, John, for the above two pictures!!
There is a really good Picnic at Hanging Rock Forum here
Hanging Rock is, indeed, a real place.
The view of the rock itself, and the view from the rock are both quite beautiful.
My You Tube Video for Picnic at Hanging Rock
There is now an excellent site which deals with the "missing minutes" from the new release of Picnic at Hanging Rock. You can go here . It's very well done.
A review of the movie by Tony Whitaker is here
Sandra from Germany has her new picnic site here.
Note: the information on this page is the most correct I have been able to come up with. In some of the materials below the information stated might differ from this page but this is the page that should be considered as the most accurate.