I write "trails" as there is more than one. Although there's no map for the preserve and no guidebook covers the trails, I was fortunate enough to get advice on the options. A resident of Shippensburg I met that morning told me there were two choices. "The easy trail is the one with the blue blazes. Remember, blue equals boring. It doesn't pass any of the cascades as it climbs South Mountain. The other trail crosses the stream again and again, although its usually going to be on your left. You are going to get wet, but you'll see the waterfalls."
The first water trial was getting to the trail. After you walk down a short hill you come face to face with Tumbling Run. It's not very deep, but there's no easy way across. I wasn't going to try the log bridge.
Instead I waded across, and decided I'd work up to the excitement by taking blue for boring. I won't say the blue trail is boring, but I missed the stream. I turned back after a mile when I realized the trail was becoming rocks. Before then it consisted of pine and hardwood trees, with a lot of mud and swampy plants.
Turning back to the stream, I began to follow it, crossing back and forth as the brushy trail meandered along Tumbling Run. None of the falls were worth a trip individually, but as a group they were time well spent. There were so many I lost count, but for the stretch of trail I hiked I counted at least a dozen miniature cascades.
In 2010 I'd visited the stream, but didn't ford it. I was deterred by the condition of my knees, which had just completed hiking up Pole Steeple that morning and were feeling it. Now my replacement joints solved that problem, and I crossed the stream, hiked up the side of the mountain, and put in three pain-free miles surrounded by the woods and the water. Now if I had wet feet, it was because I did something, not because I was afraid and didn't.