Near the Florence Court estate, these UNESCO-listed caves are among the finest in Europe for exploring underground rivers, winding passages, and hidden chambers. Electrically powered boat tours take visitors underground, and knowledgeable guides explain the origins of the amazing stalactites and stalagmites. Tours last 75 minutes and leave at 15-minute intervals. The caves are occasionally closed after heavy rains, so phone ahead before making the trip if there’s been particularly bad weather recently. Reservations recommended.