About a one hour drive from Rincon, there are only two other places in the world where you will find a cave system as massive or dramatic as the Río Camuy Cave Park - and neither of them has a tropical underground river thundering through it! Visitors ride a trolley that descends into a sinkhole lined with dense tropical vegetation while a guide describes the sights. After a walk across ramps and bridges and through the dramatically illuminated, 170-foot high Cueva Clara, another tram shuttles you to a platform overlooking the 400 foot deep Tres Pueblos Sinkhole.

Another attraction is the Spiral Sinkhole and Cave. You can walk the 205 steps down into the sinkhole, but the cave itself is off limits to all but experienced spelunkers. The sinkhole is believed to have once been an enormous cavern, and is indeed an impressive sight. Cathedral cave is home to an enigmatic collection of petroglyphs etched into the walls by the ancient Taínos (native Indians).

The park is normally open Wednesday through Sunday from 8:30 a.m. to 4:00 p.m. The last tour departs at 3:30 p.m., or when the park reaches its daily capacity.