Tennessee Caves 2015
The Eastern Highland Rim is the line that runs roughly north / south where caves are concentrated. The Cumberland Plateau's resistant cap-rock over the top of several deep layers of limestone provides excellent conditions for cave development. Feel free to ask me about Tennessee caves. :)
The data source was the Tennessee Cave Survey's 2015 data release. I used ArcMap 10.2.2 to create the map through a series of spatial joins with 1:24k quad feature class, and a dissolved Tennessee county layer. The map projection is Tennessee State Plane, NAD83.