I've posted before that I saw something just south of Harpers Ferry in October 2002 that was definitely feline and certainly not a bobcat or a lynx (or an overgrown house cat!).

I was about 5 miles south of town at the end of a 55-mile section hike from Front Royal on a warm, clear day around noon. I came around a corner and over a slight rise and saw this animal about 40 yards in front of my on the trail. Without thinking I clapped my hands to scare it off (I should have just stopped and observed for awhile). The cat looked at me and high-tailed it into the woods with a grace and a long tail that could only be feline. It was colored a light brown, darker on top, and was the height of a large dog but not as heavily built as dogs that large. Hard to believe that it was a cougar in that area at that time of day, but nothing to this day nothing else seems to fit the evidence. As I passed by I realized that I might now be being stalked and kept an eye out for the next few miles.