Climb Down

You scramble down the rocky slope into the canyon. The walls are high enough to block the sun. The shade combined with the mist from the waterfall to make it nice and cool down here. After following the stream a little further, you come to a cave opening! There's a steel grate bolted into the rock to block the cave entrance, but both grate and lock have rusted away over the years. You're sure you could pop it open, if you wanted to enter.