A substantial limestone cave system about 5 km southeast of the city, the oldest tourist site in Cuba. The accessible galleries extend for several kilometres, though guided tours cover about 1.5 km of decorated passages — stalactites, stalagmites, crystal formations, and several underground pools. The caves maintain a constant temperature of around 24°C, a relief in summer.
Guided tours in Spanish run regularly; English tours can be arranged but require a wait or prior arrangement. The ticket office is at the site entrance, and transport from central Matanzas is available by taxi or on foot. The caves are a reasonable half-day excursion from either Matanzas or Varadero, and more interesting than the beach options for visitors who have seen enough of the coast.