YES! It is recommended that you make a reservation for the Inca Trail and pay for your entrance fee well in advance.
How to book the Inca Trail trekking?
Please, it is very much important to fill out in the blanks on the attached booking form we email you with a true and updated information so we can make your bookings with the right and appropriate information, as in case of a missing passport or wrong numbers, or name misspelling, we are not able to make any corrections on the official government documents, so you then are not able to get into the park.
How long is the Inca Trail to Machu Picchu
The Inca Trail to Machu Picchu is 42 kms (26 miles) long. Campsites along the Inca Trail are assigned by the Ministerio de Cultura Descentralizada and for this reason it is difficult to determine the distance to be covered in a day but expect to walk 6 to 9 hours per day. (http://www.tierrasvivas.com/en/before-you-go/inca-trail-faqs)