Top 5 Inventions from the Ancient Incan Empire

In the 13th century, a small group of people settled high in the Andes Mountains and later migrated down to the valley of Cuzco in southeastern Peru. Within just over two centuries, these early settlers had transformed into a powerful empire that spanned much of the Andes, with an estimated population between nine to 16 million. This was the Inca Empire, and despite flourishing from 1438 until its Spanish conquest in 1532, its achievements continue to resonate today.

The Incan empire’s vast reach is even more remarkable given that it thrived without currency, the wheel, or any form of written language.

What the Incas did have was an incredibly advanced organizational system and a virtually endless workforce, enabling them to create wonders like the breathtaking Machu Picchu. Below are five such marvels.

5: Transportation Network

While the Romans may have invented the road, the Incas revolutionized transportation in South America with an extensive network of roads and highways connecting their vast empire.

At its zenith, the Incan road system spanned nearly 25,000 miles (40,000 kilometers), with roads varying from 3 to 13 feet (1 to 4 meters) in width, ranging from basic dirt paths to finely paved stone routes. The main highways, known as the imperial road system or Capac-Nan, stretched mostly north to south, with one running along the coast and another parallel through the mountains. Smaller roads linked the two main arteries to various provincial centers. These roads were reserved for officials, with commoners requiring special permission to walk on the Capac-Nan.

Official travelers could cover around 20 miles (32 kilometers) a day along the Capac-Nan. Rest stations, or tampus, were spaced at regular intervals to provide food, shelter, and resupply opportunities. These stops were crucial for the groups, especially for the men who carried nobles in litters, raised platforms designed for transporting the elite.

4: Rope Bridges

In the harsh, canyon-filled landscape of the Andes Mountains, roads alone were not enough to provide reliable transportation. However, the Incas were no strangers to overcoming challenges, and their solution was ingenious: bridges.

Instead of the traditional stone arch bridges common in Europe, the Incas crafted suspension bridges made from rope, showcasing their mastery in weaving natural fibers. Without the need for wheeled vehicles, these bridges were ideal for foot traffic, easily supporting both people and animals.

During the bridge-building process, large ropes were made by weaving smaller strands of llama and alpaca wool, as well as grass and cotton. These ropes were anchored to stone structures on both sides of the crossing. Additional thick ropes were used to create handrails and form the bridge’s floor, which was then covered with wood and sticks.

Incan rope bridges were longer than any stone bridges in Europe at the time, stretching over gaps of at least 150 feet (46 meters). Travelers typically crossed these bridges in the morning, as the strong afternoon winds could make them sway dramatically, almost like hammocks.

Because the materials used to build the bridges were organic and biodegradable, they had to be rebuilt annually. Typically, local communities near the bridges took on this responsibility.

3: Khipus

Along with the verbal messages carried by runners, information was also transmitted across the vast roads and bridges of the Incan empire through the use of items known as khipus (sometimes spelled 'quipus').

These communication tools consisted of a central cord (the primary cord) with a series of knotted strings of different lengths and colors hanging from it (pendant cords). The strings were made from cotton or the wool of llamas or alpacas. It is believed that the number of knots, the types of knots, and their placement on each pendant cord were used for record-keeping in a decimal system. These cords were likely used to track various goods stored in qolqas, or warehouses, scattered throughout the empire.

The meaning of the messages encoded in the khipus remains a mystery to this day. However, researchers at Harvard University have initiated the Khipu Database Project. Launched in 2002, the project aims to gather all known data about khipus into a centralized database, comparing and analyzing various khipu patterns. The ultimate goal is to create a 'Rosetta Stone' that will decode the ancient messages hidden within the knotted strings.

2: Terrace Farming

Living among the steep Andean peaks, the Incas faced the challenge of farming on land that was too uneven. To address this, they developed a system of terraces, which they built across the empire, creating massive, green stairways.

The creation of these stepped terraces allowed the Incas to cultivate crops, and the ingenious design of each terrace maximized the chances of successful harvests. The construction process began with stone retaining walls that absorbed sunlight during the day and released it at night, preventing crops from freezing in the cold Andean nights. A base layer of medium gravel was laid down first, followed by a mixture of fine sand and additional gravel. Finally, topsoil was added, into which the seeds of staple crops like corn and potatoes were planted.

When the terraces occasionally failed to yield crops, the Incas relied on a method called 'the three sisters.' They would first plant corn, and once it grew to a sufficient height, beans would be added, climbing up the corn stalks. The final step was planting squash in the remaining spaces. This technique not only allowed three crops to thrive in one terrace, but also enhanced soil fertility. The beans helped by fixing nitrogen, a vital nutrient for the corn, while the squash provided natural mulch, keeping the soil moist and free of weeds.

1: Freeze-drying

NASA astronauts frequently carry freeze-dried food on their missions, but this preservation method was not invented in a laboratory. It was actually the Incas who pioneered it.

In the highest regions of the Andes, freezing temperatures are almost guaranteed during the night. The Incas took advantage of this by bringing potatoes to these freezing environments, allowing them to freeze under a cloth. The villagers would then walk on the cloths in the morning, pressing the moisture out of the potatoes. This repeated process resulted in freeze-dried potatoes called chuño.

This product had several key advantages in the Incan empire, which remain relevant today. For starters, it was lightweight, enabling soldiers to carry substantial quantities on their campaigns with ease. Additionally, chuño, like all freeze-dried foods, is remarkably durable and can last for years without refrigeration. This made it an ideal backup food source in the event of a drought, natural disaster, or crop failure. Even today, Andean highland communities turn to chuño in times of agricultural hardship. Lastly, the freeze-drying process would remove the bitter taste from certain types of potatoes, making them far more enjoyable to eat.