It was hard, and spectacular, and moving. The air was thin, the views dizzying. We saw hummingbirds and iridescent butterflies. In a ruin engulfed by cloud I stood looking over the edge and saw nothing but whiteness for miles below. The Inca must have thought that they lived at the end of the world.
When you walk with people in a place like this you are more open, somehow. Afterwards on the train back to Cusco we found a carriage where musicians had a whole excited crowd on their feet. We clustered around, half of us helpless with laughter, strangers dancing wildly while the mountains rolled by outside.