The tour begins with a gradual descent through the woods, where it is pleasantly cool in summer. There are over seventy plant species to enjoy along the way.
As you make your way down, you can hear the noise of the river bursting forth from the dark chasm. At first it is the mere murmur of invisible waters, until suddenly the Alcove appears in all its splendour, a mighty monument to Nature.
The path takes you along the edge of the river towards the Alcove then right across it. Now you are in what geologists call a « karstic steephead » and poets « the end of the world », that is, a huge semi-circular corrie from which gushes a source… or in this case, a resurgence. The walls of the corrie are absolutely vertical or steeply inclined, and 70 to 120 metres high.
When the guide has finished his commentary, we set off for the exit tunnel, dug out and constructed in 2005 – 2006. There will be one final halt to admire the dinosaur prints uncovered during the tunnelling. This brings us to the end of our visit: the tourist has spent an hour below ground and walked a kilometre through the heart of a long cavern comprising a network of 11 kilometres of charted underground passages.