In answer to your thoughts, yes this creek has been run... by some serious steep-creekers. A cave entrance is where the water you see on river right is exiting from. In dry times you can go all the way to the other entrance, or so I have been told - never done it myself. The Walls of Jericho are a stair-stepped set of ledges in an amazing limestone amphitheater. Pictures cannot do it justice. This is the 'other entrance' to the cave where the water exits below: