Most people who are interested in the Incans believe that visiting Macchu Picchu is a must. I have to agree with them, but the train journey through the Urabamba Valley may very well be the best part of the entire trip. If you have all the money in the world then take a helicopter from Cuzco to Macchu. My suggestion is that you take a dining car on one of the old Romanian trains and kick back and watch the old Incan Empire pass outside your window. It's an experience that you'll never forget!