Located just outside the town of Curití, La Vaca is the most attractive and adventurous cave in the are,a with numerous caverns filled with stalagmites and stalactites. To explore the cave you'll need to go on a guided tour (90 minutes), which can be organized in town. At one point you'll have to swim through a submerged tunnel, although there's a rope to guide you along. Wear old clothes – you'll get muddy. Not for the claustrophobic.