After arriving at Aguas Calientes, we met our guide for the afternoon, dropped off our bags at our hotel, and quickly joined a long queue to board one of the 20 or so buses that take the steep, one-lane dirt and gravel road with switchbacks to get up to the entrance to Machu Picchu. Outside the entrance we had a quick lunch, cafeteria style.

The map below shows our afternoon tour of the “high circuit” (red line) as well as our walk on the “low circuit” (blue line) the following morning. The “high circuit” provided excellent views over the citadel and toward the peaks at its northern end. The “low circuit” allowed more time in the central parts of the citadel and led us to the paths to the peaks at the citadel’s northern end.

It does not take long after arriving at Machu Picchu to understand why this Incan city, on a saddle ridge between peaks in the Andes, is one of the seven modern wonders of the world and is protected as a UN World Heritage site. Machu Picchu’s construction probably began around the year 1440; experts believe it was built as a royal Incan estate. It was abandoned – for reasons that are still a mystery – around 100 years later.

As the Incas left no written records, many questions about them and Machu Picchu remain unanswered. The Spanish, who invaded Peru in 1532, apparently did not know about Machu Picchu. It was a lost city, perhaps part of a lost region, until accidentally discovered in 1911 by Hiram Bingham, a US citizen who became fascinated with Incan archaeology while in Peru studying Simon Bolivar’s struggle in the first quarter of the 19th Century for Peru’s independence. Bingham was exploring for another Incan city when he found Machu Picchu.

Although Machu Picchu covers about 80,000 acres, the central, built-up core, or “citadel,” is compact and roughly only around 25 acres. It has sacred, agricultural and urban centers and about 200 structures in total, including houses, baths, temples and sites for rituals, sanctuaries, and one or more structures used as a calendar or for astronomical observation. There are terraced areas for animals and agriculture that supplied the city’s population – perhaps 700 to 1,000 Incas – with food. The Incas built stone canals to carry water from underground springs on the peaks above the citadel to the agricultural area and throughout the citadel. Stone fountains (16) still distribute water from the canals to the housing and sacred areas.

The citadel is an architectural wonder. Boulders were moved to the site without wheels. The stonework of the structures is extraordinary. Experts still question how the Incas could obtain such fine edges on stones that were cut to fit together precisely and without mortar. A human hair does not fit in the cracks between many of the stones.

The following photos capture all three citadel sectors, their buildings and open spaces. Among the structures pictured are the Main Door, the House of the Terrace Caretakers (or Guardhouse) in the agricultural sector, the semicircular Sun Temple (only structure with curved walls) with the Royal Tomb at its base, the Temple of the Three Windows, a fountain, and the Water Mirrors. The Water Mirrors are two bowls chiseled out of the in-place granite that became a floor. The current theory is that Incas poured water into the bowls and then at night looked into the reflections to see the moon and sky. In effect, they were astronomical observation tools.

It took until late afternoon to complete the red circuit. While heading to the exit, we noticed birds of paradise. A hummingbird went after the nectar in them. Then, after a bus ride down to Aguas Calientes, we walked to the Inkaterra Machu Picchu Pueblo Hotel, which is on a 12-acre mountainside reserve close to the train station at the far end of town. We thought about noise from trains keeping us up at night; our stucco, rustic casita was 100 yards from the tracks running through the center of the narrow town. Fortunately, it was quiet as there are no trains at night and even during the day there are just a few. The Peruvian dinner at the hotel restaurant was excellent. From our table we could see the rocky bed of the Urubamba River. We returned to the room and lit the wood in the fireplace.

We slept well and had an early, excellent breakfast at the hotel before walking to where buses line up to take visitors, who have timed tickets, to the citadel. Our tickets had early times. In what was a full morning, our guide led us through the low circuit (blue line on map above).

As mentioned above, at the citadel’s northern end is a path leading to a guarded entrance that the map labels “control booth.” After the booth are trails that on the left lead up to Huchuy Picchu and on the right up to Huayna Picchu (aka, Waynapicchu). Huchuy Picchu’s peak is not much higher (160 feet) than the citadel. The round trip is a little more than one mile and can be traveled quickly. On the other hand, Huayna Picchu’s peak is, at 8,835 feet, almost 1,000 feet higher than the Machu Picchu citadel. Estimates to climb to this peak and return begin at three hours.

A Machu Picchu entrance ticket can include a hike up one peak or the other, and only 200 people are allowed to climb Huayna Picchu a day. When we arrived at the control booth in mid-morning after completing the blue circuit, we discovered that our tickets were for Huchuy Picchu. This disappointed Tiernan as our guide from the day before said that our tickets included the climb up Huayna Picchu. I tried to solve this by buying, at the control booth, a ticket for Tiernan for the Huayna Picchu trail. Unfortunately, all 200 of that day’s reservations for the trail were taken.

Thus, Tiernan, our guide and I walked up the shorter trail to Huchuy Picchu. As my knees were quite sore by then — Machu Picchu has lots of stairs and the trails are on hard ground and rocks — I went part way up and then sat on a rock to enjoy the views until Tiernan and the guide finished their climb and returned, which they did quickly. While on the Huchuy Picchu trail, Tiernan decided that the guide and I would together exit through the control booth while he surreptitiously crossed over to the trail to Huayna Picchu so that he could also climb that peak. The photos he took show that he succeeded; the views were amazing and the trail was steep. And, he was up and back in less than 90 minutes! During that time, I wandered through other parts of the lower circuit, marveling at the architecture and views toward the valley and Urubamba River below.

After Tiernan’s hike, we met as agreed on the path to the exit. We bussed down to Aguas Calientes and stopped for lunch at a restaurant in town recommended by our guide. He called ahead to make sure we would get in during the busy lunchtime, and even got us a table overlooking the Urubamba River. We talked for a while with an interesting man (Gregg Lukenbill, a well-known entrepreneur and former owner of an NBA team) sitting with a tour group at the table adjoining ours.

Following an enjoyable lunch, we walked to the train station; the hotel sent our bags there. There was a big crowd waiting for several trains to leave Aguas Calientes that afternoon. After some delays, we boarded our train and it slowly departed around 3pm.