Wet Caves of Bonaire: Pos di Wajaka

If you ever heard somebody saying that Bonaire is like a “Gruyere cheese”, you better believe it!

Most of the island is limestone, a soft sedimentary rock that is easily weathered by water courses. Rainfall, underground water and the sea itself can dig through it, creating a variety of geological formations and karst landscapes.

Pos di Wajaka is the biggest known inland wet cave there is in Bonaire (but not the longest). It was formed by a long dissolution process that shaped the limestone into a system of caves. These underground vaults eventually collapsed, widening the cave until it reached the surface, thus creating an entrance.

This is also the deepest known wet cave of Bonaire, with -38 meters at its deepest point.

Although its existence was known by geologists and topographists in the beginning of the 20th century, the cave remained unexplored and undocumented until  the 80s, when a the first team of cave divers  performed the first dives.

Other exploration teams followed ever since, making the first rough maps and  laying the exploration line that we can still see today. The cave is explored in its majority, with the exception of a couple of deep and very dangerous galleries.

Three layers of water are clearly noticeable: the first layer is fresh water, rich in tannic acid (0-6 meters approx.), followed by a thick layer of brackish water and hydrogen sulfide acid (6-12 meters approx.). The last layer (12-38 meters approx.) is essentially salt water. These layers can change after a rainy season.

The cave displays very spectacular but fragile decoration (except for the deeper sections) and serves as one of the few natural water wells for the animals that live in the area. Visitors might disrupt their behavior and deny the access to this precious water source.

*PLEASE note that these caves are not “open” to the general public. Further survey and research should be done, and visitors can severely compromise this process and their own safety.