There are some things in life that appeal mainly to the connoisseur: others you would have to have a heart of stone not to be touched by. Machu Picchu belongs to the latter category. It makes a huge impression on all who see it. However, while it is both possible and pleasant to wander around the ruins in a dream-like state, soaking up the atmosphere, most people would appreciate the Incas' achievements all the more if they understood more about the functions of the various buildings and the problems that had to be overcome, e.g. in supplying the city with water. I have visited Machu Picchu twice and considered myself fairly well informed but learnt a great deal from each chapter of this book. Anyone who reads the book, and better still takes it along and uses it at the site in the manner intended by the authors, will get even more out of their visit than they would otherwise. Next time I go Machu Picchu, whenever that will be, I will see things in a new light.