Thank goodness for mate de coca and our tremendous guide, Vidal. I walked right past the oxygen station in the airport - I probably will take a few breaths on my next visit. The effects of altitude are curious, but the energy of anticipation and our our amazing guide are powerful!! Very attractive town square with many restaurants all competing for our attention. Numerous hilly sidestreets that need to be explored, too. I ate a guinea pig. Don't ask .... !!