Caves of Remouchamps (Remouchamps, Belgium)

Des grottes de Remouchamps are really a hidden treasure in the Belgian ardennes. That is, if you like dark clammy spaces. I do.

The caves boast the world's longest continuous underground navigation (sounds a bit like the guiness record of fastest time to enter a suitcase (true story)). 

There is a boat ride that you can take on level 2 of the caves, with living creatures like frogs and shell fish in the water.

And on level 1, you'll see fossils with the most spectacular stalactices and stalacmites, rendered even more spectacular by the light show set up inside the caves.

i'll let the pictures speak for themselves.