Some trips have additional fees. (All participants must be at least 6, but some extreme trips have additional age requirements.) Park naturalist Coy Ainsley, who helps organize the event and head up the herd of faithful volunteers from such groups as ESSO Grotto, Dayton Underground Grotto (DUG), the Ashland Cycling Enthusiasts and many others, said they are hoping to draw in 450 people this year.