Kentucky Park That Has the World's Longest Caves

Word Meaning:

MAMMOTH — Any species of the extinct genus Mammuthus, of large, usually hairy, elephant-like mammals with long curved tusks and an inclined back, which became extinct with the last retreat of ice age glaciers during the late Pleistocene period, and are known from fossils, frozen carcasses, and Paleolithic cave paintings found in North America and Eurasia.

Definitions from Wiktionary.