We anchored Pantagruel, our 60-foot classic wooden yawl, in 4 meters of water, close to the ranger station just visible among the undergrowth, and took our dinghy to the shore, where a wooden pier jutted out from a small palm-tree-lined beach. The two rangers didn't speak any English, and our Spanish is very limited, but one of them beckoned us to follow him around the corner to an entrance to a series of caves. He led us inside and proceeded to give us an impromptu guided tour. The ranger pointed out interesting limestone formations along with faces etched into the stone walls — pictographs and petroglyphs drawn by native Taino people hundreds of years ago — and tracked down small bats hanging upside down in the nooks and crevices above us. We wove our way in and out of openings in this underground cavern, admired pools of water, clambered up steep rock faces after our guide and swung down on tree vines.