For less experienced ones, vertical horizon offers many tours where everyone can find the underground experience.
And for those who do not want to tire:
One of the most beautiful and most famous in the region just 50 km from the house. Do not forget to book as places are limited. Tel: 0561058837 http://www.grands-sites-ariege.fr
For lunch and a good meal : "La petite Auberge de Niaux." (Tel: 0561050909)
It is 47 km from the house. On the way to Mirepoix and Carcassonne, take a detour.
Accessible with a road along the river Arize through a natural tunnel. It has been for very long time an asylum for animals (rhinos, bears, mammoths ... ) and for men (Magdalenian to the Huguenots). http://www.grands-sites-ariege.fr
At 60 Kms from home. There is the longest navigable underground river in Europe. Call to reserve at 05 61 65 04 11
A tour is guided and commented on 60 m underground, it will interest especially children because the visit is comfortably seated in a boat of 12 people.
You follow the underground river about 1.5 km. The course exceptionally long and varied, leads you from rooms to galleries, decorated with a multitude of concretions.
At 52 km from the house. At Ussat les Bains. It has huge rooms and a network of long galleries, it is the largest in Europe open to the public. Located near the bathes of Ussat. According to the legend, it houses the tomb Pyrene (Hercules was in love with her). This cave is ranked Guinness World Records (the largest cave in Europe). Circuits 1h, 1h30, 2h, 2h30, 3h, take you on the trail of mysteries, stories and legends that surround the site. Rooms with magnificent marble and rare minerals are accessible during visits 3h 5h 7h or (on reservation).