Kondalilla Falls & Obi Obi Gorge. With this one, you can either rock hop/swim through the creek, or follow the Great Walks path. The path is a lot easier, but also less scenic (still beautiful though).
You can either start the trail at the Kondalilla Falls carpark or at the Baroon Pocket Dam carpark. It’s a long one so we recommend leaving a car at one end if you’re not up for the return walk (or get someone to pick you up). It’s 15km+ return depending on which path you choose.

Travel time from Brisbane: 2hrs.
Trail Distance: Time: 15km & 5hrs.
Difficulty: Moderate.