Keywords: Mammoth Cave River Styx.png River Styx a partly subterranean waterway emerges onto the surface in Mammoth Cave National Park Kentucky own 2007-04-29 Huw Williams Huwmanbeing 37 11 13 8 N 86 6 30 2 W region US-KY_heading SE Files by User Huwmanbeing Karst springs in the United States Karst topography in the United States Mammoth Cave National Park Underground rivers and lakes |