Hike your way up to the clifftop cave of Cueva Ventana, one of Puerto Rico’s top attractions, located in the Arecibo region of karst limestone peaks. After a short hike, shine a flashlight on bats and spiders as you learn from a naturalist guide about the cave’s formation and the Taíno petroglyphs carved inside. At one end of the cave, enjoy a window-like view of a lush valley and the Caribbean Sea.