Take the time to walk around the site; there are many places to see and explore.
Although it is not necessary, taking a guided tour does provide a deeper insight into the ancient city, its uses, and information on the geography of it. Also, be sure to wake up early to miss the thousands of people that visit the site each day, or stay till closing time.
The first buses start running at 5:40AM, which will give you an hour or two in the pleasant light of dawn but before the full force of the sun begins hammering the mountainside. (If you plan to stay past 10AM, sunblock is requisite.)
- Temple of the Sun
Near the summit of the main city, the stonework on the temple is incredible. Look closely and you will see that there are a variety of stone walls throughout the city. Most are rough stones held together with mud, the common stone walls found throughout the world. But many buildings or parts of buildings are done with the more distinctive and impressive closely-fit stonework. The temple is the absolute pinnacle of this technology. Observe it from the side, descending the stone staircase in the main plaza.
- Temple of the Three Windows
- Main Temple
The tour guides will try to tell you that this was a temple, but look closely: between the wings of the condor is a chamber with grooves cut in the stone to secure manacles, a walkway behind where a torturer may walk to whip the prisoner's backs, and a scary looking pit to let the blood of prisoners drain. Clearly the condor was a symbol of cruel justice, but a santized version is told for the benefit of middle-aged tourists and their children.
The following sights involve some legwork:
Walk back up the Inca trail away from the site and up the hill to the Sun Gate (or Inti Punku); from here you can see back down each valley offering excellent views. It's a gentle walk (probably 45 mins tops round trip) and well worth it. If you stay in Aguas Callientes, it is possible to get here early enough to catch the sunrise from here.
Walk up Waynapicchu (in Spanish Huayna Picchu); this is the "second" hill seen in the many photos. Its a steep but short walk offering very impressive views over the site. Well worth the effort! Waynapicchu also has ruins atop its peak.
As of November 2006, visitors are no longer accepted after 1 p.m. to start the trail, and all visitors must be out by 4:00p.m. Only 400 visitors are allowed to enter this trail each day. Buses begin leaving for Machu Picchu at 5:30. A line forms early at the checkpoint to the trail. At 7:00 A.M. 400 ticket numbers are issued and the first of batch of 200 hikers is slowly released. The second group of 200 can start any time between 10:00 and 11:00 A.M.. On busy tourist days, the limit will be reached by 7 or 8 A.M.. It is recommended that you go straight here first thing. You will be required to sign in; remember your number (or the time you signed in) so that you can find yourself in the book to sign out again.
The climb is steep and at times exposed, and takes about 1 hour each way. Some portions are slippery and steel cables (a via ferrata) provide some support. Decent footwear is important. There is an extremely narrow passage near the summit (a cave). Two cautionary notes: The hike is somewhat strenuous and not advised for visitors who are elderly, pregnant or have heart/lung conditions. Also, the steep stairs and cliffs you must walk along at the summit can be terrifying for those who are afraid of heights.
If you have some time at hand, or long for a sparkle of solitude, you can also walk to the Moon Temple (Templo de la Luna) and the Great Cave (Gran Caverne). It's a long walk and adventurous hike involving several ladders. Some may find that the sites aren't really rewarding, but unexpected wildlife can be seen (wild spectacled bears have been reported). This hike is also quite interesting because partway through you leave behind the mountain terrain and enter a more conventional forest. The caves can be reached either by hiking down the trail from the peak of Waynapicchu (which includes some semi-harrowing but fun near-vertical descents) or by the split from the main Waynapicchu trail (look for the sign that says Gran Carvern). Remember that it is much easier to descend from Waynapicchu than to ascend from these temples. Be sure to bring plenty of water and snacks for this long hike. The hike from the summit to the caves and back to the checkpoint takes about two more hours.