We have left the jungle’s slow moving brown river behind us and are entering the cave. In front of me, a pillar of rock that looks like petrified silt rises up out of the cave floor. On top of it is a stone formation that almost looks like a statue of a naked lady, all green with algae. Above, the vaulted roof of the cave is covered in lime stone formations hanging down like curtains. Behind, the jagged mouth of the cave is silhouetted against blue sky.