While this was my first experience underground, Fuentes and his wife Virginie have shown hundreds of people this unique environment since 1992. "The oldest person to go was 74," Fuentes said in his limited but enthusiastic English, as he helped adjust my safety belt before we started out. When I had arranged the equipment to his satisfaction, he clapped me on the shoulder and went to help another person. We were all equipped with a hardhat, light and safety belt with snaps for connecting to the ropes which provided safeguards at steep places on the trail through the cave. When we began the ascent back up the cliff of the main chamber, my companion, a retired teacher of 67, began to show the strain of the trek and stopped often to rest. Fuentes noticed this and dropped back to help, sending me ahead with his wife and the others while he assisted my friend. Most of our group were teenagers, but four were adult chaperones and other than fatigue, there were no ill effects from the experience.

When I arranged for the visit, Fuentes had suggested wearing coveralls and rubber boots, the same outfit he and his wife wore. But most of the group wore shorts or jeans and T-shirts and running shoes, which proved adequate. Clothing quickly dried in the hot summer sun once we left the cave. I made do with an old sweat suit but did buy some inexpensive knee-high rubber boots. In the end, I could have done without the boots because inevitably I stepped in a hole in the river and the water poured in over the tops. However, the water was not so cold it numbed my feet and the temperature underground was cool but comfortable