National Parks Traveler notes that a pollution advisory has been issued.

Well, today comes word that pollution levels at Mammoth Cave are so bad the superintendent has warned park visitors.

Levels of ozone and particulate pollution at the park are forecast to pose a threat to the health of park visitors, the park said in a release this morning.
Mammoth Cave officials say visitors and area residents might want to take it easy until the pollution levels decrease.

Who knows, maybe GoLite will come out with a fashionable line of outdoor respirators.