The cabin where Lincoln was born, then the longest cave system on Earth
KEKX Addington Field Elizabethtown is closest to Abraham Lincoln Birthplace National Historical Park: a neoclassical memorial by John Russell Pope, later architect of the Jefferson Memorial, encloses the symbolic log cabin, with 56 steps up to it, one for each year of Lincoln's life; he was born here February 12, 1809, and the family worked this farm until he was two. About 50 nautical miles south, KBWG Bowling Green holds two destinations, one underground and one over it: Mammoth Cave National Park, 426 mapped miles and the longest known cave system on Earth, still being surveyed, which the enslaved guide Stephen Bishop mapped in the 1840s and called a grand, gloomy and peculiar place; and the National Corvette Museum, where a sinkhole swallowed eight Corvettes from the Skydome floor on February 12, 2014, Lincoln's 205th birthday. Karst country keeps its own calendar.