She went hiking on a common trail, and she was less than a mile from a parking lot. Usually mountain lion attacks happen when mountain lions wander in human territtory.
Actually, the majority of mountain lion attacks happen when humans go on hiking trails exactly like she was on. She was unprepared to protect herself, or her dog. In celebrating the heroism of the dog, we should always remember that she was an idiot.
If you haven't visited that area of northern california you may not know
how wild and desolate that area is.