Cave of the Winds

Cave of the Winds, buried beneath the shadow of Pikes Peak, is the oldest attraction in the region. Each year 200,000 spelunkers descend hundreds of feet into the bowels of the Earth to investigate stalagmites, stalactites and other cave phenomena such as flowstone, coral-like anthodites, cavern fungus and even cave centipedes - there are more than 3,000 different types of insects living deep in complete darkness.
For more, go to:
http://www.coloradosprings.com/articles/cave-11282-tour-water.html