The Mount Gravatt Caves are something of a mystery: many people talk of them but there’s little online evidence to show they actually exist.
Well they do exist, and I’ve been inside them.
The best way to find them is start at the Gertrude Petty Place Picnic Area and follow the signs along the Federation Trail. Just after turning right at the t-intersection, where the stairs going up begin, an unmarked side trail leads off to the left (going back downhill) – follow this unmarked trail and you’ll get to the entry of the caves at the bottom of the hill. The link to this spot on Google Maps is here.
There’s a keep out sign, which was vandalised when I visited, and not much stopping you entering the caves.
Once inside you’ll find lots of rubbish and what appears to be a makeshift campsite/fire:
The coolest part of the caves (for me) was looking up through the holes in the cave ceiling and seeing all sorts of plants growing above you:
I’d recommend avoiding walking around the area above the caves (which is fenced off) to avoid accidentally falling into one of these holes.