The botanic gardens in Brisbane are pretty cool. The walkways throughout are well planned and all the trees are labelled with what kind of plant they are which makes the whole thing pretty educational.
The highlight of the walk around for me was the giant Bayan figs with their down-growing roots which start as tendrils from the branches. Once they hit the ground the tendrils dig in and start to grow into what looks like tree trunks.
The largest fig has hundreds of these 'trunks' growing into it and it's super impressive to look at.
If you're in the gardens you should definitely wander over and check it out.
The pin on the map is exactly where the trees are!