Marakoopa Cave is the most atmospheric of the Mole Creek show caves, with underground streams, chambers, flowstone, and a glow-worm display that gives the visit its quiet drama. Entry is by guided tour, which is a good thing here: the cave is fragile and much easier to understand with someone explaining the formations.
Book ahead in busy periods and bring a layer, even if the day outside is warm. If you only have time for one cave near Mole Creek, this is usually the one to choose.