Sure, you could pay the $19 US to take the 25 minute bus ride up to Machu Picchu, but consider instead the hike up the Camino Peatonal (Pedestrian Trail) to the ruins. It is a heart pounding and legs screaming walk of just over a hour up (only about 45 minutes down). This hike will warm you up for the harder ones above on Huayna Picchu or Montaña Machu Picchu. This hike through the rainforest will give you the opportunity to see many of the birds that bird watchers come to Peru for. Many hikers begin at 5:00 am, when it is still dark, to make it to the ruins when they open at 6:00 am. It is an exhilarating trip that will allow you to be the first of the day to experience Machu Picchu while it is peaceful. To get to the Camino Peatonal follow the road from Aguas Calientes to the checkpoint and the bridge across the Urubamba River. Cross the bridge and follow the well marked trail to the Machu Picchu entrance.