Quadirikiri Cave
Arikok National Park has three ancient caves under its protection, Huliba (aka Tunnel of Love) is no longer open to the public for environmental reasons, but Fontein and Quadirikiri are. Quadiriki is the best bet if you only have time to visit one as it has natural skylights within which are ethereal and enchanting and make for excellent photographs. Be forewarned that flash photography is not permitted as it disturbs the hundreds of resident bats that make this cave their home, but don't worry, they are harmless and sleep all day. Park rangers at the entrance will take you on a free and informative guided tour. Wear closed-toe shoes, the interior is rocky and ground bugs live there, too.