Machu Picchu Facts: Engineering, Nature and Numbers Behind the Inca Wonder

Engineering Facts About Machu Picchu

Machu Picchu's engineering is its most remarkable feature: Inca builders placed an estimated 60 percent of their construction effort underground, in foundations, crushed-stone fill and drainage layers. That hidden work keeps the site from sliding off its ridge despite heavy rain, which is why buildings still stand after more than 500 years.

• Walls lean slightly inward and doors are trapezoidal, which helps them resist earthquakes.
• The finest walls are fitted so tightly that a knife blade will not slide between stones.
• Terraces have layers of large rocks, gravel and topsoil that drain rainwater.
• More than 100 drainage channels carry water away from buildings.
• Stone was quarried on site, so blocks did not travel far.

These figures come from engineering studies by hydrologist Kenneth Wright and colleagues, and are rounded estimates.

Facts About Earthquakes and Fault Lines

Machu Picchu sits where geological faults cross, and research presented in 2019 suggested the Incas chose the spot partly because fractured rock was easier to quarry and channeled water. The mortarless walls can shift during earthquakes and settle back, a technique Peruvians call dancing stones.

Several major earthquakes have struck the Cusco region since Inca times, including a severe one in 1950, yet the finest Inca walls at Machu Picchu remained standing. Following the Machu Picchu rules and regulations helps protect these walls.

Facts About Water at Machu Picchu

Machu Picchu has a spring-fed water system that still works. A stone canal about 2,500 feet (750 m) long carries water from a mountain spring into the site, where it flows through a chain of 16 fountains. The first fountain sits beside the emperor's residence, so he received the purest water.

The canal's gentle slope was calculated so water moved steadily without eroding the stone, a feat modern engineers still admire.

Nature and Wildlife Facts

Machu Picchu lies inside a protected Historic Sanctuary of about 126 square miles (326 km²), listed by UNESCO for both culture and nature. Its cloud forest is home to spectacled bears, the Andean cock-of-the-rock, Peru's national bird, hundreds of orchid species and hummingbirds. The llamas on the terraces were brought in by people.

• Spectacled bear: South America's only bear lives in the sanctuary forests
• Andean cock-of-the-rock: Bright red national bird of Peru
• Orchids: Hundreds of species reported in the sanctuary
• Vizcacha: Rabbit-like rodent often seen sunning on walls
• Llamas: Introduced, they help keep grass short

Numbers and Records

Machu Picchu's key numbers: about 200 buildings, an elevation of about 7,970 feet, a UNESCO listing in 1983 and a place among the New Seven Wonders since 2007. Before the pandemic it received about 1.5 million visitors a year, which is why daily caps and timed tickets now apply.

• Elevation: About 7,970 ft (2,430 m)
• Height above the river: About 1,300 to 1,500 ft
• Huayna Picchu summit: About 8,835 ft (2,693 m)
• Machu Picchu Mountain summit: About 10,111 ft (3,082 m)
• Visitors in 2019: About 1.5 million

Elevations are rounded; see our guide to Machu Picchu elevation and altitude sickness.

Astronomy and Sacred Design Facts

Machu Picchu was designed with the sky in mind. The Temple of the Sun has a window that lines up with sunrise on the June solstice, and the Intihuatana stone is thought to have served ritual and calendar purposes. Surrounding peaks were worshipped as apus, protective mountain spirits.

Some buildings frame mountains like picture windows, showing how Inca architects blended stone with the landscape. The meaning of these sites is debated, so guides present several interpretations. Huayna Picchu, one of those sacred peaks, can be climbed today; see our Huayna Picchu hike guide.

Fun Facts About Machu Picchu for Kids

Fun facts for kids: the Incas built Machu Picchu without wheels, iron tools or mortar; llamas roam the terraces like lawnmowers; the city has its own water fountains over 500 years old; and Huayna Picchu has a temple carved into a cave. Kids also love that a famous explorer was guided there by a local boy.

Families planning a visit can read our guide to Machu Picchu with kids.

Machu Picchu Myths That Are Not True

Several popular Machu Picchu claims are myths. It was never lost to locals, Hiram Bingham did not discover it, it was not a city of chosen virgins, aliens did not build it, and it is not sinking because of tourists, though erosion and crowding are real concerns managed by visitor limits.

Prefer to have it all arranged? Our Machu Picchu day trip from Cusco covers transport, tickets and a licensed guide.

• It was a lost city: Local farmers always knew it
• Bingham discovered it: He publicized it in 1911, guided by locals
• Mostly women lived there: Early bone analysis was later corrected
• Built by aliens or giants: Built by Inca workers with stone tools
• It was the last Inca refuge: That was Vilcabamba, elsewhere

The full story is told in our Machu Picchu history guide, and the basics in our guide to what makes Machu Picchu famous.

Lesser-known corners hold more surprises, from the Temple of the Moon cave shrine to the narrow Inca Bridge on the western cliff.