Indian Echo Caverns

Indian Echo Caverns is an historic show cave in Derry Township, Dauphin County near Hershey and Hummelstown, Pennsylvania in the United States. The caverns were mentioned in an article by the Philadelphia Philosophical Society as early as the 1700s.The limestone cave tourist destination has been considered "a living cave" because its formations continue to grow. It is open for the public to visit daily via guided tour, except for Thanksgiving, Christmas and New Year's Day. Hours vary by season, and admission rates vary by age.

Source: Wikipedia