I seem to remember reading a couple of books where a young girl(?) goes back in time from (then) modern day Sydney to about a hundred years before, using a Morton Bay fig tree as the time travel device! Does anyone else remember it?
Riddle of the Trumpalar and Challenge of the Trumpalar by Judy Bernard-Waite.
"When twins Cass and Carl vowed to save an ancient Moreton Bay fig tree from destruction they did not realise it was the beginning of a journey that would take them literally inside the tree and from there back in time to the Sydney of the ..."
Playing Beatie Bow? Never read the book, but they forced me to repeatedly watch the very poor film in school.