The climb to Third Pass is a gentle one but it becomes quite narrow as it winds along the ledge. This unnerved me a bit, but others don't seem to mind at all. At the top of the pass is a flat area which makes a good camping spot if it is late in the day.
Next stop on the trail are the ruins at Puyopatamarca, or Cloud Level Town, where water runs through carved stone channels down a long series of steps. When I was there, the channels ran very full, the sound of rushing water keeping time to the excitement pulsing through me to walk these steps, built by the Incas, all the way down to the base of the mountain.
There were baths here in Inca times. The nobles bathed at the top of the springs, where the water was clear, lesser folk at the next level and the lowest classes at the lowest level, where the water had been pre-used.
Unless you run down the steps, as some porters do, it will take you about two hours to reach the bottom. This may be hard on the knees!