Pennyroyal Plateau

The Pennyroyal Plateau or Pennyroyal Region, often spelled Pennyrile,[1] is a large physiographic region of Kentucky that features rolling hills, caves, and karst topography in general.

It is named for Hedeoma pulegioides (the American pennyroyal), a wild mint that grows in the area.

The Pennyroyal is often thought by non-geologists to include the West Kentucky Coal Field of Pennsylvanian age, located in the northwestern area of the state, as the southeastern part of the Illinois Basin.

Numerous other caves exist in the Pennyroyal, where some of the most intensely cave-forming limestones of the world are to be found.

[4] Where the capping sandstone is intact, the land surface is usually forested, rugged hills.