This 268-acre park contains one of the world's largest cave networks. A tram takes you down a trail shaded by bamboo and banana trees to Cueva Clara, where the stalactites and stalagmites turn the entrance into a toothy grin. Hour-long guided tours in English and Spanish lead you on foot through the 180-foot-high cave, which is teeming with wildlife. You're likely to see blue-eyed river crabs and long-legged tarantulas. More elusive are the more than 100,000 bats that make their home in the cave. They don't come out until dark, but you can feel the heat they generate at the cave's entrance. There's a picnic area, cafeteria, and gift shop.
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