The Underground River Walk is a 4.5km loop track that will take you through a variety of landscapes, and offering stunning views - including Bilsons and Haunted Gorge Lookouts.
Commencing at the Gorge Day Visitor Area, where there's ample parking and toilet and picnic facilities, you'll head down to the Underground River, where you'll traverse a mass of granite boulders before heading up again.
The Underground River is where you can undertake guided river caving tours with a number of local operators.
You'll complete the loop when you join the Gorge-Lake Catani Track, which returns you to the Gorge Day Visitor Area. Or, for a longer hike, you can continue walking towards Lake Catani.
Allow up to two hours to complete this hike, and be prepared for a few uphill and downhill sections.