Maybe half a mile past the cave visitor's center. Parking is a small pull off on the left, then you walk back down canyon to the climbing spot. It's a bolted sport route that can be top-roped by scrambling up a crack behind the wall. I think it's close but shy of 100 feet. Probably closer to 90 feet. I've got a 60 meter climbing rope that I have used for a double-rope rappel there. When set with the middle of the rope at the anchor both halves will reach the bottom with rope to spare.
Edit: The sport climb is only about half the height of the wall. You top-rope the route by scrambling up the crack, rappelling from bolts down to chains bolted into the wall about mid-way down. Set your climbing rope at the chains then rap to the bottom.
Where are you from? Hit me up in a PM or add me on Facebook and maybe I could meet you.
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