Hiked this with our Scout troop. It is essentially three miles from the parking lot on the ridge to the parking lot at the ampitheater. This direction it is mostly downhill and drops roughly 600 vertical feet over 1.5 miles. The return to the rim parking lot is a decent climb with several switch backs. If you are not in shape plan on the ascent taking a bit longer than normal. We were there in winter and the bathrooms at the ampitheater were closed, so we had to pack in water for the trek. Make sure you hit the restroom before you head out because there are none along the way except for at the ridge parking lot. This is a great morning trail to take if you are camping in the canyon and want to a good warm up for your day. Not sure any other trail in the park covers as much vertical feet in such short a distance.
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