Extending for 840m between Río Cumayasa and Río Soco, this lighted and well-marked massive underground cavern complex is off the highway some 20km west of La Romana. More than 500 pictographs and petroglyphs can be seen on the 45-minute guided tour (some English is spoken); the tour is included in the entrance fee so there’s little reason to wander around on your own.
The best way to get here is to take your own car, though taxi is also an option. Or you can try any guagua shuttling between La Romana and San Pedro de Macorís and hop off at the cave's highway turnoff.