In reading the etymology of "mammoth" I quickly learned that the word meaning "huge," is derived from the description of huge tusks found in Siberia. You can delve deeper into the word origins but the important thing to remember is that there were no mammoths in Mammoth Cave. On offer instead is the longest cave system on the planet. With mind boggling inner spaces and passageways wider than most streets on the east coast, Mammoth Cave is. Also, plenty of lovely hiking paths as well as canoeing along the aptly named Green River. Kentucky is beautiful and the roads are a pleasure to drive on, just watch out for random firework displays and police roadblocks.