BARBADOS – This is a deep island.

While so much goes on above ground, there’s a lot happening under the surface as well.

And far underground in the heart of inland Barbados lies Harrison Caves, subterranean caves formed by erosion of the limestone and shell rock left behind as Barbados rose out of the sea.

The island of Barbados is unique to all other Caribbean islands by the way it was formed.

The Atlantic and Caribbean plates met right at this point, and the resulting uprising of the sea floor, coral and sediment formed Barbados.

The limestone and sediments of shells and rock absorb, filter and store fresh water like a giant sponge. Barbados water is clean, abundant and tastes great.

In fact, 85 percent of Barbados drinking water comes from underground aquifers.  The purity of the water is managed and protected with great effort.

These caves are wonders, full of colors, lights and hues you rarely see on a Caribbean island.

Above: stalactites and stalagmites meet to form what called the village

Above: Karst forming on the cave walls

But when it comes to cave exploration, Harrison Caves is a worthy adventure from any hotel on the island.

It’s a great rainy day adventure and a wonderful experience for the whole family.

There are two ways to explore the caves.

There is a one-hour tram tour with very little walking and a 4-hour eco adventure.

On the eco-adventure you crawl through narrow passages, underground streams and dark caverns like Ole Sorenson did when he mapped the cave in 1974.

Above is the original entrance to the caverns used by the explorers.

It’s the perfect place to get lost.

And it’s another reason why Barbados isn’t quite like any other island in the region.