On a trip such as this, one of the best ways to experience spontaneity is to go on every early morning option that is offered. Yesterday we had a chance to sleep in until 8:15 )which would have been so nice!) or get up early for a 7 AM departure and scenic drive to Ollantaytambo. Naturally, I took the early option, even though we did not return to our rooms in Cusco until 10 PM. Have a look.
ignimbrite, which makes for great building stones.