A mecca for speleologists, the caves beneath the 390-meter (1,184-foot) Barra Honda Peak were created millions of years ago by erosion after the ridge emerged from the sea. You can explore the resulting calcium carbonate formations on a guided tour, and perhaps catch sight of some of the abundant underground animal life, including bats, birds, blindfish, salamanders, and snails. The caves are spread around almost 23 square km (9 square miles), but many of them remain unexplored.
Every day from 8 am to 1 pm, local guides take groups rappelling 18 meters (58 feet) down into Terciopelo Cave, which shelters unusual formations shaped (they say) like fried eggs, popcorn, and shark's teeth. You must wear a harness with a rope attached for safety. The tour costs $31 per person (minimum of two) including equipment rental, guide, and entrance fee. Kids under 10 are not allowed into this cave, but they can visit the kid-size La Cuevita cavern ($5), which also has interesting
stalagmites. Both cave visits include interpretive nature hikes. The caves are not open during the wet season, for fear of flooding.
If you suffer a fear of heights, or claustrophobia, the cave tour is not for you, but Barra Honda still has plenty to offer, thanks to its extensive forests and abundant wildlife. You can climb the 3-km (2-mile) Los Laureles trail (the same trail that leads to the Terciopelo cave) to Barra Honda's summit, where you'll have sweeping views over the surrounding countryside and islet-filled Gulf of Nicoya. Wildlife you may spot on Barra Honda's trails include howler and white-faced monkeys, skunks, coatis, deer, parakeets, hawks, dozens of other bird species, and iguanas. It's a good idea to hire a local guide from the Asociación de Guias Ecologistas. The park has camping facilities, and the ranger station, open 8 am to dusk, has potable water and restrooms.