Two kilometers northeast of Venado (Spanish for ‘deer’) along a good dirt road, these caves are an adventurous excursion into an eight-chamber limestone labyrinth that extends for almost 3km. A bilingual guide leads small groups (limit seven) on two-hour tours through the darkness, squeezing through narrow passes and pointing out the most interesting rock formations (an altar, a papaya) while dodging bugs and bats (12 species in all – the vampires have darker poop from their iron-rich blood diet). Rubber boots, headlamps and helmets – plus a shower afterwards – are provided.
You’ll definitely want to bring a change of clothes.
Better to spring for their photographer to take some snaps (US$20) than to lose your precious phone in the murky waters. Trust us.
Any tour operator in La Fortuna can arrange this trip for you. If you’re driving yourself, the caves are well signed from Hwy 4. One bus at 9am comes straight here from La Fortuna (US$2.75, one hour). Otherwise, other Upala-bound buses can drop you at Jicarito, 9km from the caves. From the Jicarito cruz (crossing) it's simple to catch a lift uphill from one of the local farmers. Cash only if paying at the caves.
There's also a pool and restaurant here.